Brake Fluid?
Brake Fluid?
Well my earlier post regarding my brake problem has turned into new pads, rotors and calipers on the rear. Seems like a great time to flush and refill with better fluid. I've searched but there are too many threads to read, I've got my guy on hold before getting new fluid, he's talking silicone based, what is the recomendation, I know I've seen Q45 tech or someboby give a solid oponion, I just can't find it quickly.Thanks, Lee
Use either ValvolineSYnPower DOT 3/4 saturated wet bp 343F, dry bp 502F..best off-the shelf brake fluid you can buy.
Or,... with some time and effort to find MOTUL 600 which is very expensive and more of a race fluid so its more hygroscopic and will need changing more often that your SynPower DOT3/4.
but it's dry bp is 600F.....
I use the ValvolineSYnpOwer DOT3/4 and I drive (and brake) very hard.
Fred...
Or,... with some time and effort to find MOTUL 600 which is very expensive and more of a race fluid so its more hygroscopic and will need changing more often that your SynPower DOT3/4.
but it's dry bp is 600F.....
I use the ValvolineSYnpOwer DOT3/4 and I drive (and brake) very hard.
Fred...
Fred, thank you very much for the quickness of your reply. Your first recommendation is exactly what he is going to use. He had found it out on his own, but I feel better confirming he's right. Funny story, he was aware of Scottsdale as the source for parts, his price is the same as ours, that means we are getting wholesale as he has a BIG shop. And we got a new board member when he saw how fast I got my answer here, he was not aware of the site. Onr of the really great things about this site is that even if you are having someone else do the work, you can very quickly discover here what the CORRECT way to do it is and with the correct materials, very reassuring!
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Even with the best brake fluid money can buy. Always change it at every pad replacement and when it changes color from clear to amber or amber to light brown.
As with all fluids, color changes are the key........when they change a little get them out of service.
When you wait too long on brake fluid you sometimes have to change the master cylinder because you have allow the seals to degrade so badly you can new get clear fluid.
As with all fluids, color changes are the key........when they change a little get them out of service.
When you wait too long on brake fluid you sometimes have to change the master cylinder because you have allow the seals to degrade so badly you can new get clear fluid.
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Even with a 340F wet/550F dry one must assume something like 440F average after 6 months.A single 80 mph stop will raise the oem pads to 400-450F [in summmer 100F ambient][If you haven't used the brakes in 10 minutes at speed]...........therefore by 5-8 minutes AFTER the stop the heat has soaked thru the pads [insulators] to the backing plate onto the piston and into the brake fluid.
Highly likely that the brake fluid is at boiling point or very close........surely not ready and able to do it again soon.
Worst case is stopping quickly off Interstate and into rest area, quick trip to restroom and back accelerating out the on ramp......you may have less than optimum brakes for 5 minutes till the air flow cools things down. 20 minute stops are better!
There is always a time lag after braking before things return to normal temperature.
Obviously 550/600F capacity is a lot better than 400F but that means changing fluids every 6 months or less.
The oem pads are optimized to stop best at 300-400-450F but used fluid is not!
http://www.seinesystems.com/BrakeFade.h ... htmCastrol SRF is the wet KING at 518F but costs $70 per liter.
Is $70 dollars per year cheap to save a wreck probably!http://www.racerpartswholesale.com/srf1.htm
Highly likely that the brake fluid is at boiling point or very close........surely not ready and able to do it again soon.
Worst case is stopping quickly off Interstate and into rest area, quick trip to restroom and back accelerating out the on ramp......you may have less than optimum brakes for 5 minutes till the air flow cools things down. 20 minute stops are better!
There is always a time lag after braking before things return to normal temperature.
Obviously 550/600F capacity is a lot better than 400F but that means changing fluids every 6 months or less.
The oem pads are optimized to stop best at 300-400-450F but used fluid is not!
http://www.seinesystems.com/BrakeFade.h ... htmCastrol SRF is the wet KING at 518F but costs $70 per liter.
Is $70 dollars per year cheap to save a wreck probably!http://www.racerpartswholesale.com/srf1.htm