Brake fluid

[hauss]

Crap you guys are scaring the hell out of me. I just changed out my slave cylinder and used dot 4. I do not have willwoods but my master cylinder for the brakes is clear my car is a 2012 backdraft . My rear wheels will lock up under heavy braking could the previous owner used the wrong fluid?

[tocheck]

Originally Posted by hauss

Crap you guys are scaring the hell out of me. I just changed out my slave cylinder and used dot 4. I do not have willwoods but my master cylinder for the brakes is clear my car is a 2012 backdraft . My rear wheels will lock up under heavy braking could the previous owner used the wrong fluid?

I have a 2012 also. DOT 4 is the correct fluid. I also had rear brake lock up issues (made for a few terrifying moments on track). I ended up going to a more aggressive front pad, since we don't have bias adjust.

[hauss]

Originally Posted by tocheck

I have a 2012 also. DOT 4 is the correct fluid. I also had rear brake lock up issues (made for a few terrifying moments on track). I ended up going to a more aggressive front pad, since we don't have bias adjust.

Are you saying dot 4 for brakes in the 2012?

[cycleguy55]

Worth reading before switching to DOT 5:

DOT3/DOT4 to DOT5 Brake Fluid Conversion
by Dave Barbieri

Since I don't do 'conversions', I wanted to talk to some of our brake vendors (TX & CA) and get my facts straight. Here's the procedure recommended:

1. Use a turkey baster to suck all the old fluid out of the master cylinder reservoir. Fill the reservoir with rubbing alcohol. Get about 5 bottles; yer gonna need 'em. 8-P
2. Bleed the system, just like you would normally. Keep bleeding each wheel cylinder/caliper until only rubbing alcohol comes out. When all you see is only clean, clear rubbing alcohol, you're thru with the flushing.
3. Take all the brake lines loose at both ends. Use filtered, dry compressed air to blow out all alcohol. The lines must be free of all traces of alcohol.
4. Remove the master cylinder and wheel cylinders/calipers. Disassemble each component, clean thoroughly with either hot soapy water/hot water rinse or with a commercial non-filming brake cleaner. Dry each part and reassemble using DOT5 brake fluid as lubricant.
5. Components such as the combination valve will have alcohol in them from the flushing procedure. Blowing them out will be pretty touchy. Too much air and you 'blow out' the valve, too little and you don't get rid of the alcohol.
6. Re-install all the parts, fill the reservoir with DOT5 fluid, and bleed as normal.

There's not complete agreement on how DOT5 reacts with DOT3/4. Some tech reps said it forms a gummy residue that affects brake action. Two stated that the DOT5 would simply 'flush out' any traces of alcohol/DOT3/4 during the bleeding process. Since there's not 100% agreement, (and I'm both anal-retentive and paranoid when it comes to brakes), I listed the full procedure.

Do you really, reeeelly wanna do this? DOT5 is typically used in heavy eqyuipment, military vehicles, and (some) antique vehicles. All share the same characteristic of sitting for long periods of time. DOT5 gets rid of any concern about moisture absorption while sitting idle.

DOT5 is expensive and a PITA; I think you'll spend a lot of time and $$, only to be disappointed with the actual performance gains.

DOT3/DOT4 to DOT5 Brake Fluid Conversion

[hauss]

Originally Posted by patrickt

Well, I guess if I had a BDR...

I have seen the front end of your car I have some left over screen from a screen door I fixed.I would gladly send it to you along with some black zip ties . I have also seen your roll bar so I think the look would fit your car.

[cycleguy55]

MPB's (Master Power Brakes) take on DOT 5: https://techtalk.mpbrakes.com/brake-...an-i-use-dot-5

[tocheck]

Originally Posted by hauss

Are you saying dot 4 for brakes in the 2012?

That is what I use. I use high temp because I track the car occasionally. Dot 3 and Dot 4 are compatible. I flush the entire system every year.

When I first got the car, I was wringing my hands over the type of fluid the car had. I did a lot of reading and learned that mixing brake fluid with water would tell you if it was glycol ether based (dot 3 & 4) or silicone (dot 5). Dot 5, the water and fluid don't mix, it globs up.

That being said, I am not a mechanic. Always do your own research and double check what any of us say.

[jimbo01]

motal 5.1 is used on motorcycles and is compatible with dot 3. Dot 5 is not to be used with dot 3 or dot 4. Motal dot 5.1 does not damage the paint if it comes in contact. I use it in all applications which use brake fluid.