Racing brake fluid

[Megamike55]

I will be taking my CT5 BW to the track in Homestead, FL end of February, and was wondering if the car equipped with carbon ceramic brakes have racing brake fluid already in them?

 

[MatthewAMEL]

No, they do not. Swap to good dot4.

My personal fave is Castrol SRF. Motul 600/660 is also good.

 

[strohw]

If you're group 3 or 4 I don't think you need to change fluid. That said, I personally run Endless RF650.

 

[LF4472]

There's a track prep section in Owner's Manual somewhere around page 220.

 

[OldGoat]

I believe rear diff fluid R&R is also recommended after track use.

 

[MatthewAMEL]

I believe rear diff fluid R&R is also recommended after track use.

Manual (pg 193 and pg 207) says @1,500 miles before 1st track event, then every 24 track hours for diff.

Transmission fluid change every 15 track hours. Seems to indicate same interval for A10 and M6. (pg 193)

See...this is why we need a dedicated performance supplement.

 

[Megamike55]

Yep just confirmed it all - thanks! FYI - in the 2023 owners manual the Competitive Driving and Track info starts on page 246

 

[MatthewAMEL]

Decided to stop complaining about it and try to do something. Here is start of an unofficial HP Supplement.

 

[OldGoat]

Decided to stop complaining about it and try to do something. Here is start of an unofficial HP Supplement.

 

[Megamike55]

Awesome!

 

[Mcard23]

SRF is my go to, worked well last season on the blackwing (as expected).

 

[Neebs]

How much brake fluid do you need to flush given brakes share reservoir with clutch? Is 1L sufficient?

 

[strohw]

How much brake fluid do you need to flush given brakes share reservoir with clutch? Is 1L sufficient?

I haven't changed mine yet but I'll assume it's the same as a lot of cars that share the clutch. You want to go in with 1.5L to 2L. That's the same amount on hand you'd want with something like a Camaro or Cayman.

 

[Carguyshu]

Decided to stop complaining about it and try to do something. Here is start of an unofficial HP Supplement.

I believe the brake burnishment procedure is only for the 5s with CCB

 

[MatthewAMEL]

I believe the brake burnishment procedure is only for the 5s with CCB

It's one of those quirks of the CT4/5 manuals.

You are correct, the CT5 manual says for J57 (CCB) brakes...however, the CT4 manual has the same procedure listed and it doesn't get CCBs. I think it's a mistake. But the page before that (CT4 manual pg 187) talks about burnishing the iron (JE2) brakes before high performance driving. In any case, Iron and CCBs need break-in before spirited use.

IMHO, there should be a procedure in both CT4 and CT5 manuals for iron brake and in CT5 for CCB. As it stands, there is a CCB-only procedure in CT5 manual and a iron and CCB procedure in CT4 manual. That's clearly a mistake.

 

[poor-sha]

All brakes should be bedded before track use, but it’s more important with CCBs. The procedure is always to get them hot enough that they lay down a transfer layer and then let them cool without braking so it stays there.

 

[Daijoubu]

There's one big thing about high temp brake fluid that is often overlooked. The higher temp brake fluids absorb water much faster than factory fluids. I'm not sure if it's really linear, but generally the higher the boiling point, the more hygroscopic the fluid is. I swapped to Castrol SRF, but that also means changing it out every year, or more.

 

[Carguyshu]

There's one big thing about high temp brake fluid that is often overlooked. The higher temp brake fluids absorb water much faster than factory fluids. I'm not sure if it's really linear, but generally the higher the boiling point, the more hygroscopic the fluid is. I swapped to Castrol SRF, but that also means changing it out every year, or more.

While this is true the SRF wet boiling point is extremely high & can take on a lot of moisture before the boiling point has gotten lower then OEM. If you’re tracking the car you want SRF in there bc it will last an entire year while other track fluids need more frequent change. I buy mine from fcp euro as I have an AMG I sometimes track. Free lifetime replacement on all things including fluid. You just send the old bottles back with old fluid (you pay that shipping) & they’ll send you back new.