Marv

I need to bleed my brakes (replacing the flexible brake lines).

However, I am not sure what brake fluid is in the car. Seems clear in color, so I was thinking it is DOT 4.

On the 2004 does the clutch and brakes share the same reservoir?

Is there a way to determine if the existing brake fluid is synthetic or not?

barchstein

Hello,
What's important is to to start in the furthest caliper from the break fluid reservoir (rear right if left hand drive.)
and if you do a full flush, then no need to worry about what liquid was in the car.
Best is to buy a motive break bleed tool kit. and do a full flush...
There are 2 possibilities for the break fluid. either you want something that will last but you dont track the car, i would go with a premium brand in DOT5.1.
Or you track the car often and you need a high performance Dot4 with a higher boiling temp.

You can bleed the clutch too if you want but that is required only in specific cases and I'm less familiar with them.

(FYI, seems like a full break fluid flush will take 3liters between what's in the break lines and the liquid in the reservoir.)

Toby Pennycuff

@Marv for many years the only brake fluid carried on the PMNA trucks was the Endless RF-650 brake fluid - Brake fluid | Endless Brake Technology Europe AB (endless-brake.info). It went into many of the Cups. I run it in all my cars, street and track, and have NEVER had a soft pedal because the brake fluid gave up the ghost. It was the only brake fluid I would run in my 996 Cup. It's available on Amazon - . I'm just a customer, but highly recommend it.

Toby

rodneyr

Castrol SRF is what I have been using for many years. It is a great value and a high quality product.

Marv

How much fluid to do a full flush?

rodneyr

I just use the one liter Castrol SRF bottle. I use the motive bleeder and bleed our around 8 ounces per caliper (4 inside / 4 outside) starting from the right rear, left rear, right front and left front last.

Marv

Also, my shop dropped my engine last year and among other things, replaced the clutch. I am thinking they may already have flushed the system, but I will find out tomorrow what they did.

Rootwitch

I've always used SRF, but was planning to switch to Endless. Haven't made it to track for quite a while though so splurging on either of these might be dumb.

powdrhound

Endless RF650 is what Porsche Motorsport replaced SFR with as OEM fill. I've been running endless for the last 10 years and have never had a brake fade issue.

porschedog

Great info, thanks for sharing it.

Marv

If I suck out the existing fluid from the reservoir, then fill it with new fluid before starting the bleed (I have the Motive bleeder), I am hoping that 1 liter will be enough to purge and fill the brake system. Does that sound right?

powdrhound

I budget 1L to do a full flush and bleed at beginning of the season and 0.5L when doing mid season bleeds... RF650 comes in 0.5L bottles which is another reason I prefer it to SRF which only comes in 1L bottles leaving you with an open bottle.

Marv

Done. 1 liter. Thanks everyone for your help and idea!