Brake/Clutch Fluid?

[BSM 135i]

i'm going to be installing a modified CDV soon and after installed i am gonna bleed the clutch and i know that i MIGHT NOT need to top off the fluids but i am going to buy a bottle just in case and i was wondering what brake/clutch fluid should i use? i was thinking OEM brake fluid but is there any other brand that you guys might recommend?

[akak1997]

Originally Posted by BSM 135i

i'm going to be installing a modified CDV soon and after installed i am gonna bleed the clutch and i know that i MIGHT NOT need to top off the fluids but i am going to buy a bottle just in case and i was wondering what brake/clutch fluid should i use? i was thinking OEM brake fluid but is there any other brand that you guys might recommend?

Unless you're doing a full blown flush, I'd just get OEM Fluids. If you're only doing CDV, I really don't think you'll use a whole bottle, unless of coz, you messed up. I've seen post saying they got a "dead" pedal since they bleed out all the fluid.

[Lester]

Get the BMW brake fluid from your dealer.

[Call]

Never mix brands...if you are not replacing all of it then use the same that is already installed.

Call

[BSM 135i]

thanks guys! looks like im off the the dealership to buy brake fluid!

[BSM 135i]

dope the dealership just let me have a bottle

[F0Bman]

If you're going to flush it might as well run Motul. I highly doube BMW brake fluid is any different, and probably is rebadged Motul anyway.

[Lester]

Yes - but why take a chance?

[JHZR2]

ATE 400 is a good DOT4 brake fluid. So long as the same type is used, they are fully miscible and can be mixed. There is only minimal difference in additization.

I would stick with DOT4 from a fresh bottle. That is the key, as brake fluid absorbs water from the atmosphere. Only buy as much as you need, and though it is generally more expensive on a unit basis, buy smaller bottles and keep them sealed. Likely you wont use the rest in a normal size bottle for a good long while, and you should never keep it... so you end up throwing away brake fluid.

[BSM 135i]

Originally Posted by JHZR2

ATE 400 is a good DOT4 brake fluid. So long as the same type is used, they are fully miscible and can be mixed. There is only minimal difference in additization.

I would stick with DOT4 from a fresh bottle. That is the key, as brake fluid absorbs water from the atmosphere. Only buy as much as you need, and though it is generally more expensive on a unit basis, buy smaller bottles and keep them sealed. Likely you wont use the rest in a normal size bottle for a good long while, and you should never keep it... so you end up throwing away brake fluid.

thanks for the tip! i just picked up a 12oz bottle of OE fluid from the dealership, they just let me have it!

[Lester]

Originally Posted by BSM 135i

thanks for the tip! i just picked up a 12oz bottle of OE fluid from the dealership, they just let me have it!

Nice - did you tell them it was for a CDV delete?

[Lester]

Originally Posted by JHZR2

ATE 400 is a good DOT4 brake fluid. So long as the same type is used, they are fully miscible and can be mixed. There is only minimal difference in additization.

I would stick with DOT4 from a fresh bottle. That is the key, as brake fluid absorbs water from the atmosphere. Only buy as much as you need, and though it is generally more expensive on a unit basis, buy smaller bottles and keep them sealed. Likely you wont use the rest in a normal size bottle for a good long while, and you should never keep it... so you end up throwing away brake fluid.

This is what I would use if I drove in very hot climates, or in conditions where heat could be a problem, eg. long hills or track conditions otherwise a good DOT4.

[JHZR2]

Super blue is the exact same fluid at 400, just with a blue dye. Blue dye is nice to know youve swapped all the fluid out, but once it is blue in there, it is nearly impossible to get the blue dye out, even with significant fluid swapping.

[The HACK]

Originally Posted by Call

Never mix brands...if you are not replacing all of it then use the same that is already installed.

Call

There's nothing wrong with mixing brands. It's the STANDARDS you shouldn't mix, and that's only between DOT III/IV and DOT V standards since normal hydraulic fluid does not mix well with silicone based hydraulic fluid. "Mixing" fluid is one of the old tricks when people alternate between ATE SuperBlue and Typ 200 to tell when they've completed a flush (the fluid coming out will go from a light yellow to a green to a dark blue when flushing with ATE SuperBlue).

Anything that's DOT III or IV with equal or higher dry and wet boiling temperature than OEM fluid is fine. If you plan on doing high performance driving, or live in an area where the ambient temperature is particularly high with a lot of stop and go driving, you might want to consider fluids like ATE Typ 200 or Motul 600/660 where the dry boiling point is closer to 600 degrees (Typ 200 is 560 degrees, and Motul 600 is 580 degrees I think. BMW OEM fluid is rated to ~400 degrees dry boiling point and around 300 wet).