Coolants 101 – Dave’s Garage

Recently I got a question about the many different types of antifreeze available today. Specifically, what type to put in a new Honda with blue coolant. So, here it is:

Types of Coolant (Antifreeze)
Today’s coolant market is confusing. In days past all coolant was the green ethylene glycol variety, one type of coolant for every car. Now it seems that every car manufacturer has at least one color of coolant. What Type of Antifreeze Should I Use?…..All Makes and Models?…Extended Life 150,000 Miles?…..Green, Red, Yellow, Orange, Pink, Blue? There are a lot of choices of different automotive coolants today. So, which one should you use in your car? You should use what your car was made to have. However, sometimes it may be difficult to decipher what the original equipment manufacturer (OEM) used, especially if you purchased your car used.

Basically, there are three basic types of automotive coolant: Inorganic Acid Technology (IAT), Organic Acid Technology (OAT), and Hybrid Organic Acid Technology (HOAT).

IAT coolants are the “traditional green” variety used in virtually all American vehicles from the late 1920s to the mid to late 1990s. Like all antifreeze, it is naturally clear; its color comes from dye. Unlike the other types of antifreeze, it uses silicate and phosphate corrosion inhibitors to protect the metal parts of the engine and cooling system. However, these inhibitors wear out quickly, so IAT type coolants need to be flushed every two years or 30,000 miles. OAT coolants typically do not use silicate and phosphate corrosion inhibitors. Different manufacturers use different chemical additives to battle rust and corrosion, and they all dye their coolants different colors. GM’s ubiquitous DEX-COOL coolant is an OAT antifreeze dyed orange. Toyota, Volkswagen, and Audi all use their own formulas that happen to be dyed pink. Honda uses a dark green (blue) dye. OAT coolants have longer service lives than IAT coolants, needing to be flushed every 5 years or 150,000 miles. HOAT coolants use different additives than OAT, but also use some silicate to protect aluminum surfaces. Modern Ford, Chrysler, and most European vehicles use their own HOAT coolant formulas. Ford’s is dyed yellow and Chrysler’s is orange (not to be confused with DEX-COOL). Both use the marketing name of GO-5. HOAT coolant has the same service interval as OAT (5 years or 150,000 miles).

Summary:

  • IAT – Used in early to mid-late 90’s Domestic vehicles…….This type is good for our antique cars
  • OAT – Used in late 90’s GM and most Asian vehicles
  • HOAT – Used in 2000’s Fords, Chryslers, and most European vehicles.

Although you can mix coolant types without harm, it is highly recommended against. If you mix an OAT or HOAT with an IAT, you will lose the extended service life of the OAT or HOAT coolant. Some people say that if you mix these types of coolant it can result in the coolant gelling, but if you keep your cooling system well maintained, this should not be a problem.

And finally, what about the “Universal, All Makes, All Models” coolant you see stuffing store shelves? Basically, those are OAT DEX-COOL clones. I would personally steer well clear of them unless your vehicle is de-signed for OAT coolant. You should always check your owners manual, and make sure the coolant you add is the same type of coolant your car requires.

Thanks to “how-to-matthew” for information contained in this article.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Removal of Broken Studs and Bolts – Dave’s Garage

We’ve all been there, especially while working on vehicles that are driven in salt. We start to wrench a nut or a bolt, and… SNAP!

sheered boltHere, the fastener is broken off, the metal has been cleaned up and is ready for the weld.

Easy outs can work, unless they twist or snap off. Ever try to drill out an easy- out? It’s almost impossible. The metal is very hard, and when they snap, they usually give no warning. It is also almost impossible to drill and tap without going off center. I have a little trick I’ve been using for years, very handy if you have access to a MIG welder. First, weld a bulb on the end of the broken stud or bolt. The resulting heat from the weld will heat the fastener and usually break the rust bond.

broken stud boltHere, the metal bulb is welded to the end of the broken stud. While the weld is still hot, penetrating oil is sprayed on the broken stud.
Second, either place a nut over the bulb and weld it to the bulb, or latch on to the bulb with a pair of vise grips. If you elected to weld a nut on the bulb, place a box wrench over the nut.

broken bolt vice gripsAfter locking on the bulb with vise grips, the broken stud was coaxed out by gently rocking it back and forth until it easily unscrewed. You can see the shiny steel weld in the jaws of the vise grips, and the rust colored threads of the broken stud.

Soak the fastener with penetrating oil, then gently work it loose by rocking it back and forth. Now it should easily back out. This process is much easier when trying to remove a steel fastener from a non-ferrous metal (brass, bronze, aluminum, etc.) because these materials will not weld with a mig welder, and the weld will not stick to anything but the fastener. I have also welded nuts to rounded off bolt heads and nuts to facilitate their removal.

Remember, when reassembling these parts, use a liberal amount of Never-Seize, so the next time you take it apart, it will come apart.
I hope this tip helps!


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

It Pays to Know Good Parts Counter People – Dave’s Garage

No mail this month, so I will discuss the importance of a good parts counter person.

Recently, I found my self needing to borrow a car. I asked dad if I could borrow his Subaru. The A/C clutch was broken and he asked me if I could fix it while I had the car. The bearing in the clutch pulley was broken. He had taken it to the dealer, and the Subaru dealer stated that the compres-sor needed to be replaced. The compressor was fine, it was only the clutch bearing that was the problem. I pulled the bearing and was fortunate enough to still be able to read the numbers off it. I grabbed my calipers and set off to buy a bearing. The first stop was Advance Auto Parts. The guy behind the counter tried to look it up, then told me that the part was not available. He was trying to look it up by year, make, model and part. I asked him to try to look it up by the bearing number… No luck. I pulled out my calipers and began to measure it so he could look it up by size. He had no idea what the calipers were, and inquisitively asked me what they were and what they did. He then told me there was no way to look up a bearing by it’s dimensions, or by the bearing number. A quick Google search by the bearing number showed the bearing to be available. A google search is often quite helpful in trying to find an odd ball part. Having this information in hand can help the guy on the other side of the counter find a part for you. My next stop was Bond Auto. The guy quickly checked the application by looking at year, make and model, then just used the bearing number. Several minutes later he told me the bearing was available, but would take a few days to get in. He then suggested I try Bearing Specialty Supply in Williston, as they could get it faster. So, with the help of a competent parts counter guy I was able to fix the car for less than ten percent of the cost of a new compressor. If you have the time, it is usually cheaper to order a part on line. If you need the part quickly, or you are not sure what it looks like and want to hold it in your hand before you pay for it, it is better to use the local auto parts store. A decent parts person is a valuable asset; whether it is the local auto parts store or the parts counter at a dealership. A good parts counter person will often tell me if other parts are often needed, and what issues mechanics have run into when servicing a particular part. This information can be quite helpful. They can also tell me how often they sell a particular part…this is helpful information too. I have found the parts guys at both Bond and Napa to be quite helpful. The other guys… Not so much…


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

The Pozidriv Screw… Not Phillips – Dave’s Garage

pozidriv screw head
The screws have a head that looks like this:

Absent mail this month, I thought I would pass along something interesting I recently learned. Over the years I have seen a lot of screws on antique cars that I thought were early Phillips screws. I always assumed that it was a particular brand of screw. In addition to the slots for a screwdriver, there are a second set of very faint cross slots 45 degrees away. I’ve no-ticed these screws seem to be on a lot of British cars.
These are not Phillips, but rather something called Pozidriv. Here is some information and history on Pozidriv courtesy of Wikipedia:

The Pozidriv, sometimes misspelled Pozidrive, screw drive is an improved version of the Phillips screw drive. It is jointly patented by the Phillips Screw Company and American Screw Company. The name is thought to be an abbreviation of positive drive. Its advantage over Phillips drives is its decreased likelihood to cam out, which allows greater torque to be applied.
Phillips drivers have an intentional angle on the flanks and rounded corners so they will cam out of the slot before a power tool will twist off the screw head. The Pozidriv screws and drivers have straight sided flanks.

The Pozidriv screwdriver and screws are also visually distinguishable from Phillips by the second set of cross-like features set 45 degrees from the cross. The manufacturing process for Pozidriv screwdrivers is slightly more complex. The Phillips driver has four simple slots cut out of it, whereas in the Pozidriv each slot is the result of two machining processes at right angles. The result of this is that the arms of the cross are parallel-sided with the Pozidriv, and tapered with the Phillips.

This design is intended to decrease the likelihood that the Pozidriv screwdriver will slip out, provide a greater driving surface, and decrease wear. The chief disadvantage of Pozidriv screws is that they are visually quite similar to Phillips, thus many people are unaware of the difference or do not own the correct drivers for them, and use incorrect screwdrivers. This results in difficulty with removing the screw and damage to the slot, rendering any subsequent use of a correct screwdriver unsatisfactory. Phillips screwdrivers will fit in and turn Pozidriv screws, but will cam out if enough torque is applied, potentially damaging the screw head. The marker lines on a Pozidriv screwdriver will not fit a Phillips screw correctly, and are likely to slip or tear out the screw head.

There are special Pozidriv screwdrivers available from tool manufacturers. Snap-On sells an assortment with five different sizes. If you are finding a lot of these “odd phillips” screws, it may be worth your while to pick up a set of Pozidriv screwdrivers.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Test Starting an Unmounted Engine – Dave’s Garage

I hope your summer is going well… it is nice to finally get somewhat of a break from the rain. As I am sitting here typing this, I think I can actually hear the grass growing outside my window. I have been quite busy with my MG TF project, the body tub went back on the running chassis yesterday, now I am hooking everything back up and trying to find all the parts I took off last year…

This question came to me this month:

Q. I have the “sliver” of a ’25 Moon. Continental 6 motor, chassis, wheels, radiator, hood, steering wheel…umm that’s about it. I had the starter rebuilt & now want to try to see if the motor will run. The flywheel does turn & it doesn’t appear to be “stuck”. I think it’s a 6 volt system, but is it negative ground? The radiator leaks real good, too! What do I have to do to test it out? Is there a basic flow chart/ or some diagnostic chart to follow for basic engine starting? Thank you for your response.

A. To test an engine, the engine needs to be firmly mounted to something. I would recommend bolting it in to the frame. Before you attempt to start the engine, the carburetor should be taken apart and cleaned and the engine oil should be changed. You need some provision to check for oil pressure. Do you have the gauge from the car? If not, do you have a mechanical gauge? With the engine bolted down, the carburetor cleaned and the oil changed the spark plugs should be removed and the engine should be turned over using the starter until there is good and stable oil pressure. To run, the engine needs three things; air, fuel and spark. You can hook the distributor up to any coil, six, or twelve volt, positive or negative ground, the electrons do not care, and the point and condenser system will work with any combination of the above to test fire an engine. I would check the points to make sure they are clean and working first. Either wire a switch in to the wire, or hook it up in such a way to be able to quickly disconnect a wire to shut the engine down. With the carburetor cleaned you can take several feet of hose and either hook it up to the fuel pump (if it works) or si-phon fuel through the hose from a gas can to the carburetor, keeping the gas can higher than the carburetor. Since you are test firing an engine, and only running it momentarily, you can put the coolant hoses in to a five gallon pail of water. To start the engine, use jumper cables directly on the starter. The starter has permanent magnets in it so it is not polarity sensitive. Place one lead on a good ground, and the other on the starter terminal. When you have power going to the ignition coil and you are ready to start, connect the jumper cable to a battery to activate the starter. BE prepared to “pull the plug” and keep a good fire extinguisher near by! This will quickly tell you if the engine is running or not, but will not give you much information as to the condition of the engine. Since it has been sitting for so long, it will probably not run very well, and it will smoke. Taking compression readings and noting the oil pressure will give you a good idea of the condition of the engine. I would not run the engine for more than a few seconds. Best of luck to you and keep us posted with your results.

I received this tip from Ken Taplin, and I am passing it along. I do not have a cell phone or a GPS, but I know most people do. I have not tried this, but would assume that it will work since most electronics operate on low voltage DC power.

Dave, Maybe I’m the only one that didn’t know this but I recently discovered that you can run a gps and charge a cell phone just as well on 6V as 12V. I used to carry a 12V battery pack for that. You do need the right polarity and In my positive ground cars I have installed marine grade power points. The cases are plastic and therefore not grounded so you can hook up the two wires for the right polarity. – Ken Taplin Blue Hill, Me.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

JB Weld

Once again, my mail bag is empty. Since I have no questions to answer, I will write this month about a product I have used for years, but have been asked a lot of questions about lately. People have joked over the years that if it were not for “JB Weld” my cars would have fallen to the ground in pieces. In fact, there is a ring of truth to this.

“JB Weld” is a two-part epoxy product. It comes in several different flavors, but the concept is the same. There is a “JB Quick” that sets up in about five minutes, but once cured is not as strong as the original JB Weld. For applications im-mersed in water there is a JB Weld that sets up under water, appropriately called “JB Water Weld.”

JB Weld has a cured tensile strength of 3,960 psi. Though it sets up in 4-6 hours but takes 24 hours to cure. Additionally, it is non-conductive (well-insulated) and can be filed, drilled, tapped, and painted. When fully cured, JB Weld is completely resistant to water, gasoline, and about every other petroleum product or automotive chemical. This epoxy will work in tem-peratures up to 500 degrees Fahrenheit, but will fail if heated beyond this point. This epoxy sticks well to all metals. However, it does not stick to flexible rubber, leather, vinyl, canvas or polypropylene plastic.

I first used JB Weld to fix a pot metal door lock assembly in my first Subaru Legacy. Somebody recommended it, and I reluctantly tried it. Much to my surprise, it worked. Since then, I have found countless uses for it over the years. The right side horn on the MG TD I recently restored is largely made out of JB weld. The horn is a cast assembly, and the throat of the horn was smashed, though the mechanical part of the horn still worked. Unfortunately, the throat of this horn is an una-vailable part, so I decided I would try to repair it with the epoxy. Using the horn on the other side as a pattern, I was able to rebuild the throat of the horn with the epoxy. I have glued bolts on to broken-off studs and been able to back the stud out. I have fixed my wife’s stainless steel pots and pans, using it to replace broken rivets, knobs and spot welds. It has held up to both the heat and the dishwasher. I have often used this epoxy in my model-making, using it as both a glue and to make my own cast model parts. I have recently been asking people if they are familiar with this product. A number of people have told me that they use it, and use it often. Surprisingly, a few people have told me they either never heard of it, or have heard of it but never used it before.

Here are some tips for new users:

  • As with any type of adhesion, make sure the surface is clean and free of any grease or greasy residue. Clean the surface with soap and water and dry.
  • Before applying the epoxy, rough up the surface with sand paper or a wire brush and clean with acetone or lacquer thinner. Make sure you mix exactly 50% resin to 50% hardener. The mixture has to be close to 50-50 or it will not fully cure.
  • Allow the epoxy to cure before it is moved. I often use tape to hold the epoxy in place until it hardens. If this is not possible, use the JB Stick putty, as this will hold its shape until it cures.

Hopefully, if your tool box isn’t already well-stocked with JB Weld, it will be soon! It has served me very well over the years, and I’m certain you will find it as indispensable as I have, if you haven’t already enjoyed the benefits of this product.

(This column is a Q & A column with you asking me questions and after researching the answer I will reply. Any questions ‘automotive’ is fare game, I might not know the answer but hopefully I will find someone who does know.)


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

 

Why the Model T Ford was so Historically Significant

To say the Model T Ford was in influential and unique automobile would be an understatement. No other vehicle left such a lasting impact on the automotive world. This car not only made the automobile affordable to the masses, it put America on wheels and helped to define the modern, industrial and mobile American society.

Let’s take a look at some of the unique features of the Model T

  • First mass produced car on an assembly line; many production features that sped up and streamlined production, like only having one type of paint on the car, fast drying and easy to match black lacquer.
  • The model T was the first production car with a removable Cylinder head.
  • There was no water pump on the Model T. The cooling system relied on thermal cycling to achieve cooling. Ford opted for a cheaper and more reliable thermo-siphon system. Hot water, being less dense, would rise to the top of the engine and up into the top of the radiator, descending to the bottom as it cooled, and back into the engine.
  • There was no fuel pump on the Model T. The carburetor was located relatively low on the engine, and the fuel delivery was gravity fed- the down side? people often had to back up steep hills due to fuel starvation.
  • There was no distributor on the model T. There were four individual coil boxes, switched by a low voltage “commutator“ or timer. Power came either from the six volt DC battery, or the engine magneto that produced AC current. The car was usually started on battery power, then switched to the Magneto with the key on the dashboard.
  • There was no Speedometer, odometer, fuel gauge or gas gauge on the Model T. The only instrumentation was an amp meter on the dashboard.
  • The Model T had an unconventional, planetary two speed transmission. First gear was engaged by depressing the left pedal on the floor. Releasing this pedal disengaged first gear. Second gear was engaged by sliding the parking brake lever (just to the left of the driver) forward while depressing the low gear pedal. With the parking brake lever in it forward most position, releasing the first gear pedal engaged second gear.
  • Reverse was engaged by depressing a pedal on the floor.
  • The Model T had no gas pedal. The throttle was a pencil sized lever on the right side of the steering column. This unique driving arrangement puzzled many unfamiliar motorists, and the transition from a Model T to other cars could be confusing at times, resulting in many fatalities and many more spectacular vehicle crashes.

With the exception of the original Volkswagen Beetle, no car has had a higher production number than the Model T Ford. The car was produced from 1908 through 1927, with a total production volume of more than 15 million cars. At its peak of production in 1925 , the Ford Motor Company was producing more than 10,000 Model T Fords a day! The Model T was the world’s first “global car” The Ford Model T was the first automobile built by various countries simultaneously since they were being produced in Canada , England Germany, Argentina, France, Spain, Denmark, Norway, Belgium, Brazil, Mexico, and Japan.. Ford made use of the knock-down kit concept almost from the beginning of the company. Ford was so efficient, that the shipping crate for the knock down Model T was made of components that became wooden members on the assembled car.
The Model T Ford had many non-automotive effects on our society as well. Henry Ford pioneered the “typical” work week, with a Monday through Friday forty hour week consisting of five 8 hour shifts. This set up the concept of a “weekend” with Saturday and Sunday off. “Kingsford” charcoal was made from waste at the Ford assembly plant.

“Firestone” tires were the tire of choice on the Model T, giving Henry Ford’s friend Harvey Firestone business that built up the Fire-stone Rubber company. Harvey Firestone and Henry Ford developed a life long friendship and became industrial tycoons together. Harvey Firestone’s granddaughter ended up marrying Henry Ford’s Grandson. Ford and Firestone had a lasting business relation-ship that lasted 95 years. This relationship was severed with the Ford Explorer roll over problem, made worse by defective Firestone tires that would suddenly suffer severe structural failure resulting in sudden blow outs or tread separation. Ford had a defective product, the Explorer which had poor handling characteristics resulting in a tendency to roll over, and Firestone had a defective product, the Fire-stone Wilderness AT tire, a tire that was built to specifications by Ford for the Explorer. Ford and Firestone each publicly pointed the finger toward each other, and the business relationship was dissolved. Ford Motor Company ceased to buy tires from Firestone. While this very public feud was happening, the CEO of the Ford Motor Company was William Clay Ford, great grandson to both Harvey Fire-stone and Henry Ford.

I greatly enjoyed giving people the opportunity to experience a hand on test drive in a Model T at the April VAE meet. If anyone missed the opportunity, ask me and I would be happy to offer it again.
I received a nice type written note from founding member Lloyd Davis a few weeks ago. It was refreshing to read a letter written on a typewriter. Thank you Lloyd.

In closing, I want to tell you about a license plate that caught my eye on a Toyota Prius a few days ago. It was a New York plate that read “NVMYMPG.” It took me a minute, then it hit me, “envy my MPG.” With gas over $4.00 a gallon, I do.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Spring has Sprung!

Finally, after record snowfalls and a winter that ignored the calendar and continued to bombard us with cold and snow, winter seems to be finally done. This means the summer driving season is finally upon us. Before you uncover that collector car and enjoy your first drive of the season it is a good idea to give your car a good inspection. Assuming it was stored properly this should be a quick process. The engine oil should have been changed before storage, so only a quick level check should be necessary. While you are under the hood the freshly charged battery can be installed (alternatively the battery tender removed) and the cable(s) hooked up again. A quick check of the other fluids, (brake fluid, transmission fluid, differential oil and coolant) is also a good idea. Now is the time to either change any fluids that need changing, or to address any leaks. Find any rodent nests under there? I found one al-ready this spring.

I always closely inspect tires and suspension components on vehicles before they go back in service. Inspect tire side walls and tread for any damage. How old are the tires? If they are six years old or older watch them carefully, they are susceptible to sudden catastrophic failure. Finally, check the tire pressure, wheel bearings and front end to ensure every-thing is as it should be.

It is also a good idea to check the wipers and lights at this time. The surprise of finding issues while on a drive or at the state inspection, or worse yet from a policeman can easily be avoided now.

Lastly, before you hit the road, make sure the registration, inspection and insurance are all current and that the registration tag and proof of insurance cards are in the glove box. Before you embark on that first drive, test your brakes. Do you have good pedal? Is it soft, or worse yet did it go to the floor? Before you drive on the highway drive at 20 MPH or so and give the brake a good stomp. Does the car pull to one side? Do the brakes work well?

Your “every day” car should receive some attention after a winter driving season too. In addition to the maintenance mentioned above, a vehicle driven through the winter should be thoroughly cleaned and inspected. If you change your tires over from snow tires to summer tires this is the ideal time to clean and inspect your car.

Take a garden hose and get all the salt sand and mud out of the wheel wells, from inside the fenders, the bottom of the doors, hood and trunk lid, up in the strut towers and anywhere else you can think of. Check drain holes in rocker pan-els doors and quarter panels to ensure they are clear.
Generally. When I see a car similar to mine on the road that is rusty I pay attention to where that rust is and make especially sure to keep that area clean on my car.

A few weeks ago when I put the Subaru on the lift to change the tires over I was shocked to see that both rear sway-bar links were broken, and the exhaust system was just barely attached to the car. I also found a loose splash guard.

I hope you all have a happy and safe summer of driving fun!

(This column is a Q & A column with you asking me questions and after researching the answer I will reply. Any questions ‘automotive’ is fare game, I might not know the answer but hopefully I will find someone who does know.)


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

DOT 4 Brake Fluid – Dave’s Garage

DOT 4 fluid, which has a higher minimum boiling temperature requirement (446 degrees F dry and 311 degrees wet) soaks up moisture at a slower rate but suffers an even sharper drop in boiling temperature as moisture accumulates. Three percent water will lower the boiling point as much as 50%! Considering the fact that today’s front-wheel drive brake systems with semi-metallic linings run significantly hotter than their rear-wheel drive counterparts, high brake temperatures require fluid that can take the heat. But as we said earlier, the brake fluid in many of today’s vehicles cannot because it is old and full of moisture. Water contamination increases the danger of brake failure because vapor pockets can form if the fluid gets too hot. Vapor displaces fluid and is compressible, so when the brakes are applied the pedal may go all the way to the floor without applying the brakes! In addition to the safety issue, water-laden brake fluid promotes corrosion and pitting in caliper pistons and bores, wheel cylinders, master cylinders, steel brake lines and ABS modulators. FLUID RELATED BRAKE FAILURES From time to time we hear about reports of “unexplained” brake failures that caused accidents. When the vehicle’s brakes are inspected, no apparent mechanical fault can be found. The fluid level is normal, the linings are within specifications, the hydraulics appear to be working normally and the pedal feels firm. Yet the brakes failed. Why? Because something made the brakes hot, which in turn overheated the fluid causing it to boil. The underlying cause often turns out to be a dragging rear parking brake that does not release. But that’s another story. The same kind of sudden brake failure due to fluid boil may occur in any driving situation that puts undue stress on the brakes: a sudden panic stop followed by another, mountain driving, towing a trailer, hard driving, etc. A case in point: A child was killed in an accident when the five-year old minivan with 79,000 miles on it his parents were driving suffered loss of pedal and crashed while the family was driving in the mountains of Washington state. Fluid boil was blamed as the cause of the accident.

OEM Brake Fluid Recommendations

  • Acura: 36 months
  • Audi: 24 months
  • BMW: 24 months, or when indicated by Service Inspection Indicator
  • Honda: 36 months
  • Jaguar: 24 months all models except 2009 XF (36 months)
  • Land Rover: 36 months
  • Lexus: 36 months or 30,000 miles, which ever comes first
  • Mercedes-Benz: 24 months
  • MINI 24 months
  • Saab: 48 months (all models except 9-7X)
  • Smart: 24 months or 20,000 miles, which ever comes first
  • Subaru: 30 months or 30,000 miles (normal service) or 15 months/15,000 miles (severe service)
  • Suzuki: 24 months or 30,000 miles, which ever comes first (Forenza & Reno), 60 months or 60,000 miles (Grand Vitara and SX4)
  • Volkswagen: 24 months (New Beetle, City Gold, City Jetta), 36 months (all other models except Routan)
  • Volvo: 24 months or 37,000 miles (Normal), or 12 months (severe service)

Source for fluid change recommendations: Vehicle Manufacturer service information & owners manuals If motorists would only follow this simple advice to change their brake fluid periodically, they could greatly reduce the risks associated with moisture-contaminated brake fluid. You can extend the life of your brake system and likely save yourself a lot of money in the long run on brake repairs, especially if your vehicle is equipped with ABS (because ABS modulators are very expensive to replace!).

Testing Brake Fluid

Since you can’t tell how badly contaminated brake fluid is by its appearance alone (unless the fluid is full of rust or is muddy brown), the fluid should be tested unless you are changing it for preventive maintenance or as part of a brake job. There are three ways to check the condition of the brake fluid: Chemical test strips. A chemical test strip made by Phoenix Systems (888-749-7977) www.stripdip.com called “Strip Dip” can reveal the condition of the corrosion inhibitors in the brake fluid. The FASCAR chemicals react to the presence of copper in the fluid. The test strip changes color to reveal the condition of the fluid. When copper levels reach 100, it indicates the corrosion inhibitors are nearing the end of their life. If the copper level is 200 or higher, the corrosion inhibitors are worn out and the fluid needs to be changed.

Electronic brake fluid testers actually measure the fluid’s boiling point. The test takes only about a minute and is quite accurate. If the fluid’s boiling temperature is getting dangerously low, replacement is recommended to minimize the risks of pedal fade caused by fluid boil. Sources for electronic brake fluid testers include Alba Diagnostics, MISCO and OTC.

Changing Brake Fluid

When the fluid is changed, use the type of brake fluid (DOT 3 or 4) specified by the vehicle manufacturer. The cap on the fluid reservoir will usually indicate what type of brake fluid is required. You can also find this information in your Owners Manual (look under brake fluid). As any brake fluid supplier will tell you, brake fluid is NOT a generic product. Just because a fluid meets the minimum DOT 3 or DOT 4 specifications does not mean it can tolerate moisture or provide the same degree of corrosion protection as another brand of fluid. Raybestos, for example, sells a “Super Stop Super High Performance” DOT 3 fluid with a dry boiling point of 550 degree F, which meets Ford’s latest requirements. There are also high temperature glycol based DOT 5.1 brake fluids (not to be confused with DOT 5 which is silicone based). The dry boiling temperature rating for DOT 5.1 is 518º F or higher, and the wet boiling temperature rating is 375º F or higher. Some racing brake fluids exceed the dry boiling temperature rating, but may only meet the wet boiling temperature requirements for DOT 3 fluid (284 degrees). So the next time you are inspecting or servicing your brakes, be sure to check the condition of the fluid as well as the level. If you add or change fluid, use type specified by the vehicle manufacturer (DOT 3 or 4) and use the highest quality fluid you can get. And above all, remember the benefits of changing the brake fluid for preventive maintenance.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Brake Fluid 101

I was driving dad’s car hauler through Smuggler’s Notch last fall bringing a car back from Stowe when I got a sobering lesson on why it is important to replace brake fluid. As I was passing the waterfalls in the Notch, the sedan with out of state plates in front of me abruptly stopped in the middle of the road to take a picture of the waterfall. I stomped on the brakes and came to an abrupt stop. Annoying, but no big deal. Moments later as I was descending the Jeffersonville side of the notch I tapped the brake as the truck started to run away at the top of the hill. No brakes. I pressed harder and harder on the pedal, but the truck was still speeding up. I manually down shifted and continued to thump on the brake. White smoke was now pouring off both front wheels. Ever notice that there is no runaway truck ramp there? I was able to stop the truck eventually. I pulled off to the side of the road and allowed the brakes to cool. How did this happen? The truck had just had the front pads replaced. When I looked at the brake fluid instead of a clear-yellow color, it looked more like grape juice. My theory is this: The new pads were slightly wider, creating some drag and some heat. The pistons were recently pushed back in to the calipers to accept the new pads, dirty contaminated fluid probably caused some rust on the caliper bores, causing the pistons to stick a little. The heat caused the brake fluid to boil, reducing the ability of it to compress the pads against the rotors. I changed the fluid, and exercised the pistons in and out a few times. Something the shop that replaced the pads should have done.

I have been using DOT 5, or silicone fluid in the antique cars for years with good results. Silicone fluid does not absorb moisture, so is perfect for antique cars. In the last year I have done the brakes on two MG cars that had conventional fluid, and one that I had changed over to Silicone fluid in 1988. The two with the conventional fluid had considerable corrosion in both the wheel cylinders and in the master cylinder. One MG, the green 1949 TC had half of the wheel cylinder pistons actually frozen. This car has marginal brakes to begin with, with half the wheel cylinder pistons frozen it was simply unsafe. The other MG had functional brakes when it was in a bad accident in 1999. The fluid was obviously in need of replacement, because all of the pistons became seized in their bores, requiring a great deal of effort to remove. The MG with the Silicone fluid had no corrosion in the master cylinder or the wheel cylinders. This is the black 1955 that is undergoing a total restoration, so I went through the brake system replacing all the metal brake lines, rubber hoses and seals. I have heard the horror stories of how the silicone fluid dissolved rubber parts, but have never seen any evidence of that or read anything that suggests this is really possible. My guess is that these owners would have experienced this regardless of what type of brake fluid was in their car. If you use DOT 3 or DOT 4 in your antique car I suggest you replace the fluid every two years, or switch to Silicone fluid. One other benefit to Silicone fluid is that it will not harm your paint. This is a great bonus for those master cylinders that are hard to fill without spillage. Just remember the old Midas commercial slogan, “the most important part of your car isn’t what makes it go, it is what makes it STOP!”

Why Change Brake Fluid?

Copyright AA1Car Brake Fluid is a hot topic because most people don’t know why it should be changed. Did you know the average motorist who drives 10,000 to 15,000 miles a year uses his brakes about 75,000 times a year? Did you know that nearly half of all motorists in a recent Car Care Council survey said brake failure was their number one fear amongst driving emergencies? So consider this: After three years of service, the average boiling point of the brake fluid has dropped to a potentially dangerous level because of moisture contamination and may not meet minimum federal requirements for brake fluid. Probably half of all cars and light trucks that are 10 or more years old in the U.S. have never had their brake fluid changed. Yet in many European countries, regular brake fluid checks are required, and half of all cars routinely fail such tests. That’s a good case for changing brake fluid. REPLACE BRAKE FLUID Brake fluid is one of the most neglected fluid in vehicles today, yet is vitally important for safe driving. Consequently, professional technicians should be checking the fluid and recommending that the brake fluid be changed if it is contaminated. The issue is old brake fluid may not be safe if moisture contamination is above a certain level.

Brake Fluid Preventative Maintenance

Many experts have long recommend changing the brake fluid every year or two for preventative maintenance. Their rationale is based on the fact that glycol-based brake fluid starts to absorb moisture from the moment it is put in the system. The fluid attracts moisture through microscopic pores in rubber hoses, past seals and exposure to the air. The problem is obviously worse in wet climates where humidity is high. After only a year of service, the brake fluid in the average vehicle may contain as much as two percent water. After 18 months, the level of contamination can be as high as three percent. And after several years of service, it is not unusual to find brake fluid that contains as much as seven to eight percent water.

An NHTSA survey found that the brake fluid in 20% of 1,720 vehicles sampled contained 5% or more water! As the concentration of moisture increases, it causes a sharp drop in the fluid’s boiling temperature. Brand new DOT 3 brake fluid must have a dry (no moisture) boiling point of at least 401 degrees F, and a wet (moisture-saturated) boiling point of no less than 284 degrees. Most new DOT 3 fluids exceed these requirements and have a dry boiling point that ranges from 460 degrees up to over 500 degrees. Only one percent water in the fluid can lower the boiling point of a typical DOT 3 fluid to 369 degrees. Two percent water can push the boiling point down to around 320 degrees, and three percent will take it all the way down to 293 degrees, which is getting dangerously close to the mini-mum DOT and OEM requirements.

Dave’s Brake Fluid article will continue in the April Issue


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477