Hi Folks,

I am about to do a complete brake change on my 99 roadster. Calipers, Rotors & Pads. The cap on my master cylinder says DOT 3 but I see lot of DOT 4 fluid that people seem to use. I don't track my car, so what do you in the know suggest I replace the brake fluid with ? What is the difference between DOT 3 & DOT 4 ? I don't want to screw up !

I'm thinking to get two litres, will this be enough to do a complete flush ? Oh and by the way, I ordered a Motive Power Bleeder today for the job.

Thanks for your advice,

-Garry

 

use dot 4 and do not let air into the abs

 

Dot 4 is compatible with Dot 3 but it has a higher boiling point. Did you say 2 liters? That would be too much. I think the last time I did a brake job it took 4 of the small pints. Dont open the extra bottle and you can take it back (if you have the receipt). Do not use any OLD brake fluid bottle that you have laying around. Once you open a bottle it only has a shelf life of like one month. Brake fluid absorbs moisture over time.

 

Unless you do a lot of hard braking (track days or spirited mountain driving), a good quality DOT3 fluid is fine. Something like Castrol LMA or Ford Motorsorts HD fluid will work well. The Ford fluid has a wet boiling point of 290 degrees and the Castrol is 311 degrees.

If you intend on doing track days, go with a DOT4 fluid like ATE Super Blue or TYP200. This fluid has a wet boiling point of 392 degrees.

The Motive pressure bleeder will be a big help in flushing and adding the new fluid. But don't put brake fluid into the Motive tank. Just pressurize the tank to about 15-20 psi to do the bleeding. That amount of pressure will effectively bleed the ABS system along with the brake lines and calipers.

You will need to keep a close watch on the fluid level in the master cylinder reservoir so that it doesn't run dry. One liter of fluid should be enough. The Castrol and Ford fluids come in small bottles so 3-4 should be enough.

 

Valvoline Synpower DOT 3 & DOT 4 Brake fluid

 

According to a link I just read tonight on the NCM website, the brake fluid with the highest wet and dry boiling points is Castrol SRF. It's a DOT4 fluid.

 

Yes and Castrol SRF is $80 / liter. Use Castrol LMA, Valvoline Synthpower for commercially avaible DOT 4 Fluids. Or ATE Superblue or Gold 600, AP 600, Wilwood 600 or Brembo 600. Motul is also great but some times hard to get.

I use SRF in my track car, but LMA in the street vette and pick up truck.

Unless you race or do 10-12 DEs a year, SRF may not be worth the change. If you do that many events, then YES SRF is worth the change.

Personnally I do not Like Ford HD. It is great when fresh, but needs to flushed all the time to work great

 

Personally I use Valvoline for the street and Wilwood EXP for the track.

Read below to learn more

DOT 3 VS. DOT 4 and 5.1
AFCO's 570º brake fluid is a DOT 3 type fluid. However, it has a dry boiling point that is 52º higher than DOT 5.1 specifications, 124º higher than DOT 4 specifications and 169º higher than DOT 3 specifications. AFCO's 570º fluid meets or exceeds all DOT 3, 4, and 5.1 lubrication, corrosion protection and viscosity specifications.

WET VS. DRY BOILING POINT
The term boiling point when used regarding brake fluid means the temperatures that brake fluid will begin to boil.

WET BOILING POINT
The minimum temperatures that brake fluids will begin to boil when the brake system contains 3% water by volume of the system.

DRY BOILING POINT
The temperatures that brake fluid will boil with no water present in the system.

MOISTURE IN THE BRAKE SYSTEM
Water/moisture can be found in nearly all brake systems. Moisture enters the brake system in several ways. One of the more common ways is from using old or pre-opened fluid. Keep in mind, that brake fluid draws in moisture from the surrounding air. Tightly sealing brake fluid bottles and not storing them for long periods of time will help keep moisture out. When changing or bleeding brake fluid always replace master cylinder caps as soon as possible to prevent moisture from entering into the master cylinder. Condensation, (small moisture droplets) can form in lines and calipers. As caliper and line temperatures heat up and then cool repeatedly, condensation occurs, leaving behind an increase in moisture/water. Over time the moisture becomes trapped in the internal sections of calipers, lines, master cylinders, etc. When this water reaches 212º F the water turns to steam. Many times air in the brake system is a result of water that has turned to steam. The build up of steam will create air pressure in the system, sometimes to the point that enough pressure is created to push caliper pistons into the brake pad. This will create brake drag as the rotor and pads make contact and can also create more heat in the system. Diffusion is another way in that water/moisture may enter the system.

Diffusion occurs when over time moisture enters through rubber brake hoses. The use of hoses made from EPDM materials (Ethlene-Propylene-Diene-Materials) will reduce the amount of diffusion OR use steel braided brake hose with a non-rubber sleeve (usually Teflon) to greatly reduce the diffusion process.

THINGS TO REMEMBER

• Brake fluids dry boiling point is more important then wet boiling point when used in a racing brake system.
• Passenger cars very rarely will undergo a brake fluid change making the wet boiling point more important.
• Racing brake system fluid is changed often and a system with fresh fluid will most likely not contain water.
• Because of this, racers should be concerned with the dry boiling point.
• Racing fluid exceeds DOT 3, 4, and 5.1 dry boiling point specifications.
• Never use silicone based fluids in racing brake systems.
• Using racing brake fluid will increase performance of the braking system.
• Never reuse fluid. º Never mix types or brands of brake fluid.
• Use smaller fluid containers that can be used quicker.
• If fluid remains in container be sure to tightly seal and do not store for long periods of time.
• Purge system (complete drain) and replace fluid often.

Below list provided by "The ultimate brake fluid comparison chart" (I would like to add more to this).

Arranged by Dry L

• DRY:401F -- WET:284F --- DOT3 MINIMUM (GLYCOL BASE)
• DRY:446F -- WET:311F --- DOT4 MINIMUM (GLYCOL BASE)
• DRY:500F -- WET:356F --- DOT5 MINIMUM (SILICONE BASE)
• DRY:500F -- WET:356F --- DOT5.1 MINIMUM (GLYCOL BASE)
• DRY:527F -- WET:302F --- AP RACING 551 ($12.95/0.5L OR 16.9 OZ)
• DRY:527F -- WET:347F --- VALVOLINE SYNPOWER DOT3 & DOT4
• DRY:536F -- WET:392F --- ATE SUPERBLUE/TYP200 ($9.95/1L)
• DRY:543F -- WET:349F --- Endless The truth DOT 4 ($35/1L)
• DRY:550F -- WET:284F --- PERFORMANCE Friction Z rated ($6.27/16 OZ)
• DRY:550F -- WET:284F --- FORD HEAVY DUTY DOT 3 ($4/12 OZ)
• DRY:570F -- WET:284F --- WILWOOD 570 ($5.65/12 OZ)
• DRY:572F -- WET:284F --- US Brake/AFCO Racing 570 Gold
• DRY:572F -- WET:421F --- US Brake/AFCO Racing Ultra HTX
• DRY:577F -- WET:300F --- Brake Man
• DRY:585F -- WET:421F --- Earl's Hypertemp 421
• DRY:590F -- WET:410F --- AP RACING Super 600 ($16.95/0.5L OR 16.9 OZ)
• DRY:593F -- WET:420F --- MOTUL RBF600 ($12.95/0.5L OR 16.9 OZ)
• DRY:590F -- WET:518F --- CASTROL SRF ($69.00/1L 0R 33.8 OZ)
• DRY:601F -- WET:399F --- BREMBO LCF 600 PLUS ($26.75/0.5L OR 16.9 OZ)
• DRY:610F -- WET:421F --- NEO SYNTHETICS SUPER DOT 610($11.95/12 OZ)
• DRY:610F -- WET:421F --- PROSPEED GS610 ($39.95/16 OZ)
• DRY:617F -- WET:413F --- Endless RF-450 ($45/1L)
• DRY:620F -- WET:425F --- COBALT SUPER XRF [seem to no longer be available]
• DRY:622F -- WET:424F --- Endless RF-650
• DRY:626F -- WET:417F --- WILWOOD EXP 600 ($16.95/0.5L 16.9 OZ)

Arranged by wet boiling point:

• DRY:401F -- WET:284F --- DOT3 MINIMUM
• DRY:550F -- WET:284F --- PERFORMANCE Friction Z rated
• DRY:550F -- WET:284F --- FORD HEAVY DUTY DOT 3
• DRY:570F -- WET:284F --- WILWOOD 570
• DRY:572F -- WET:284F --- US Brake / AFCO Racing 570 Gold
• DRY:577F -- WET:300F --- Brake Man
• DRY:527F -- WET:302F --- AP RACING 551
• DRY:446F -- WET:311F --- DOT4 MINIMUM
• DRY:527F -- WET:347F --- VALVOLINE SYNPOWER DOT3 & DOT4
• DRY:543F -- WET:349F --- Endless The truth DOT 4
• DRY:500F -- WET:356F --- DOT5.1 MINIMUM (GLYCOL BASE)
• DRY:500F -- WET:356F --- DOT5 MINIMUM (SILICONE BASE)
• DRY:536F -- WET:392F --- ATE SUPERBLUE/TYP200
• DRY:601F -- WET:399F --- BREMBO LCF 600 PLUS
• DRY:590F -- WET:410F --- AP RACING Super 600
• DRY:617F -- WET:413F --- Endless RF-450
• DRY:626F -- WET:417F --- WILWOOD EXP 600
• DRY:572F -- WET:421F --- US Brake/AFCO Racing Ultra HTX
• DRY:585F -- WET:421F --- Earl's Hypertemp 421
• DRY:593F -- WET:420F --- MOTUL RBF600
• DRY:610F -- WET:421F --- NEO SYNTHETICS SUPER DOT 610
• DRY:610F -- WET:421F --- PROSPEED GS610
• DRY:622F -- WET:424F --- Endless RF-650
• DRY:620F -- WET:425F --- COBALT SUPER XRF [seem to no longer be available]
• DRY:590F -- WET:518F --- CASTROL SRF

 

Thanks for the replies guy's.

I saw at Napa auto parts they had the Castrol LMA in regular and Synthetic. Is the synthetic better ?

Also, I would think I would want to flush out all the old brake fluid first before adding in the new, correct ? Do I hook up the Motive pressure bleeder, pressureize it and then open the bleeder screws and let the system purge, or do I start adding the new fluid in with the old and just watch what comes out the bleeder screws to be the new fluid ?

Sorry for all the questions, but I have never done this before and I want to learn to do more on my car rather than take it to the stealer if you know what I mean.

Lastely, If I choose to go with something like the ATE Blue, is there a cheaper place to buy it on line ?

Thanks again,

-Garry

 

Gary

I thought Castrol LMA was a synthtic.

Get a turkey baster or 50 cc surynge for mixing gas and oil for a 2 cycle motor. Putt 4" of Tygon tubing on the tip. 1/4" ID

Car should be on four jack stands and all four wheels off

Suck out the old brake fluid from the MC.

Fill the MC with new brake fluid.

Start with right rear.

10 mm wrench.

attach bleed bottle, Old clear soda bottle Coke or Pepsi with hole though top and 12" of tygon tubbing though.

attach end of tygon tube to bleed screw.

Pump up Power bleeder 15-20 psi 25 is fine too. No less then 12 psi.

OPen bleed screw and watch the brake fluid drain out. 1/2 turn until brake fluid is flowing.

Make sure tygon tubing is tight on the bleed screw

When clear brake fluid is coming though the tubing. tighten bleed screw, check pressure in Power bleeder tank.

May have to put more new fluid into MC tank. Dont let MC run dry.

( NOTE: DO NOT PUT BRAKE FLUID INTO POWER BLEEDER TANK. That gets very messy and wastes brake fluid )

Do rear two calipers. PUT CAP BACK ON MC
Then pump brake peddle 3,4, 5 times too assure brake peddle is firm.

Put more brake fluid in MC, put on power bleeder, pump up to 15-20 psi and do front two calipers.

Remove Powerbleeder cap, put up to 3/4 full of MC

NOTE: FOR ANY TRACK USE DO NOT FILL MC. PUT NO MORE THEN 3/4 FULL OF MC. Hot brake fluid expands. If the MC is full, where will that HOT brake fluid go?

Bake fluid is costic and WILL eat paint. Keep lots of rags around.

Put wheels on and go for short drive to check brakes.

If peddle is not firm, put the car back on four jack stands and re bleed the brakes.

Good Luck

 

AU N EGL,

Thank You very much for the detailed instruction, that gives me a good handle on it now.

Cheers,

-Garry

 

I was very curious about brake fluid, so I gathered all of the specific manufacturer information for the brake fluids I knew of. Here is an image of the graph from the spreadsheet that contains the specific information:



The most current spreadsheet is available here:
Link to spreadsheet This is in Excel 2007 .xlsx format, so you will need to download the Microsoft Office Compatibility Pack if you are using a previous version of Microsoft Office.

If you want all of the MSDS and PDS for these products, go here:
Zip file with all data, caution this is 6MB

I now use ProSpeed GS610 and have had great results. GS610 Link

 

Good spread sheet.

a few things. Brake fluid is hydroscopic, ie it absorbs water. Brake fluid is called WET or saturated with water at 3-4% of the total fluid content.

How long does it take for brake fluid to be saturated or WET? 30 days from when the bottle is opened. That is not even used. Just opened and the seal is broken. Never store an opened bottle or can. Disposes of properly.

So when you come right down to it, toss out the DRY brake fluid levels, unless you race and change you brake fluid several times each WEEKEND between track stints.

Look at WET boiling points only. Look for brake fluid with a WET boiling point as close to, if not above 400* F

 

Guy's I thought of one other thing that I am not clear on;

Since I am removing my Calipers and replacing them it seems like I would want to purge all the old fluid out, but at the same time I am hearing advise not to let the master cylinder get totally empty. I have a vision of when I disconnect the calipers from the brake lines that fluid is going to go everywhere. And what about re-connecting the brake lines to the new calipers. If it's seeping out I don't want to get the fluid on the new painted calipers. Would it not be advisable to remove most of the fluid via a turkey baster as advised, hook my Motive brake bleeder to the MC, pressurize it, open the bleed screws until all the fluid is purged, then install the new calipers and follow the bleeding proceedure ? Obviously this would allow air into the system which one reply said to not let happen. How the heck does one remove a caliper and install a new one without getting fluid on the new calipers ?
Also, on the brake line connections, do you use teflon tape on the threads or ?

Sorry for sounding so thick on this, but I really don't want to screw it up.

Cheers once again,

-Garry

 

Gary

Why are you changing your calipers? are they spreadding?

If you do no worries. If you can cap off the lines, do so.

Or when on the occasion some one did let the MC dry out,

that is where the 25 PSI in the pressure bleeder comes from, AND putting the wheels back on and going for a very VERY SLOW drive to pump the brakes. Both get fluid though the ABS module in the Caliper.

Put the car back on the jack stands, and rebleed all four corners again.

I have never used a Tech II, dont think I know what one looks like. Never had a problem

 

I bought a new set of Z06 calipers to replace the stock ones. I didn't want to take the time to remove my stock ones and paint them or send them out for powder coat. This way I can install the new ones and take my time fixing up the stock ones for re-sale.

When you say cap the lines, I assume you mean the opposite end of the line from where it screws into the caliper ? Upon re-install do I usr teflon tape on the threads or a thread sealer ?

Thanks !

 

Yes the brake line that goes INTO the caliper.

No thread tape, no real need for thread sealer. just make sure the threads are clean and dry.

Putting ON Stainless steel brake lines too? if not this would be a good time.

 

Hi, I'm not a brake expert, but have done quite a few brake jobs and fluid changes in my time. From everything I've read on the subject, synthetic silicone based brake fluid is absolutely not recommended for cars with ABS systems. The reasons stated are that the pulsing of the ABS can introduce air pockets into the system and cause all sorts of problems getting the air out again. And the pedal will be hard and require more pressure. LMA dot 4 is a good choice. Dot 3 is OEM and for most street driving is also a good choice. The silicone based synthetics are great for restored antiques, and classics, preventing rust in the lines and wheel and master cylinders, but not for modern ABS systems. So unless there is new knowledge out there, that is what I've read on the subject.
Luck TO ALL

 

Is the GM/late model Ford bleeder the one to use from Motive? Are speed bleeders needed like those form Earls?

I'm also getting ready to swap calipers and am looking for all info possible.

 

Do not let air get into the system above the Brake Pressure Modulator Valve or you will end up going to the dealer to get it bled. Keep the master cylinder reservoir full with the cap fastened and quickly change the brake lines over one caliper at a time. A little brake fluid on the Z calipers will not hurt them if you clean it off once you get the brake lines tight. When the brake line is open the fluid will gravity feed through the line but you will not lose that much if you work quickly. If you are not changing brake hoses the seepage will be at the caliper. If you are changing brake hoses you can have the new hose pre-installed in the caliper and the seepage will be at the other end of the brake line. Brake cleaner will get rid of any spilled brake fluid.

Bill