When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I had my brakes flushed on a '17 AMG-GTS. I used Castrol SRF as per recommendations from forum members. The mechanic returned the un-used portion to me (see pic). I was under the impression a one liter bottle was required to flush the brakes but I have about 375ml left over. Is this about right?
When you bleed brakes, it gets "subjective" how much fluid is enough to clear the entire line to the bleed nipple. You look at the fluid coming out and decide when it looks like new fluid.
When I bleed my brakes I go overboard (I'm retired and have tons of time ..LOL). So, I'll easily push two qts through; or in other words, I keep bleeding until I use up all the fluid.
No judgment on what I see left in that container. The tech might be confident the lines were completely flushed...and I bet he is way busier than me...
Thank you for the response. I've driven about 100 miles since the flush. Pedal feels firm, but have not hit the track yet.
Had Motul 660 previously. Pedal went soft toward the end of my 4th 20 minute session at Sebring. To be honest, I think it was my fault. I should have been jabbing the brakes when approaching a turn. Instead I was riding them as I tried to judge distance/time/turn-in.
Scheduled for an HOD day at Sebring on the 17th of Dec. Will report back.
The entire content of the brake system is approx. 500ml. Did you flush everything with 625ml?
Feasible if the liquids have a striking difference in color. Otherwise you need more around 1000ml to be on the safe side.
Castrol SRF is like stock, yellow. Maybee your old fluid was dark.;-)
Tip:
Today you bleed with pressured brakefluid on the expansion tank. When replacing brakefluid, first suck the expansion tank emty.
So you don't mix the old with the new brake fluid. It's also faster.
A positive side effect: you definitely need, less brake fluid.
Ran 5 sessions of 20 minute heats at Sebring yesterday. After the 3rd session I noticed the brake pedal didn't feel as firm. I had to press the pedal an additional inch to inch and a half to effectively slow the car down. When I got off the track I came to stop, put the car in neutral and pumped the brake pedal a couple times and it firmed up hard. In fact, it momentarily locked the brakes but released when I added throttle.
I'm using Castrol SRF. Is it possible the brake lines are expanding? Has anyone used the braided stainless brake lines offered by Renntech? In reading the product description, it states the braided lines will eliminate the 'spongey' feel with the pedal. Here's a link for reference...
Ran 5 sessions of 20 minute heats at Sebring yesterday. After the 3rd session I noticed the brake pedal didn't feel as firm. I had to press the pedal an additional inch to inch and a half to effectively slow the car down. When I got off the track I came to stop, put the car in neutral and pumped the brake pedal a couple times and it firmed up hard. In fact, it momentarily locked the brakes but released when I added throttle.
I'm using Castrol SRF. Is it possible the brake lines are expanding? Has anyone used the braided stainless brake lines offered by Renntech? In reading the product description, it states the braided lines will eliminate the 'spongey' feel with the pedal. Here's a link for reference...
Ran 5 sessions of 20 minute heats at Sebring yesterday. After the 3rd session I noticed the brake pedal didn't feel as firm. I had to press the pedal an additional inch to inch and a half to effectively slow the car down. When I got off the track I came to stop, put the car in neutral and pumped the brake pedal a couple times and it firmed up hard. In fact, it momentarily locked the brakes but released when I added throttle.
I'm using Castrol SRF. Is it possible the brake lines are expanding? Has anyone used the braided stainless brake lines offered by Renntech? In reading the product description, it states the braided lines will eliminate the 'spongey' feel with the pedal. Here's a link for reference...
Since today in the age of ABS no one brakes directly (except when the ABS fails), these brake lines do not change anything.
A difference may be feel with an ABS-free, 40 "brake line, on a motorcycle hand brake cylinder.
- Greater braking efficiency
Why ??
- Superior resistance to abrasion and corrosion...
This is also never a problem with the org. brake hoses.
Also installed other Teflon brake lines. There are good reasons for that. But never the ones from advertising.
All DOT 4 brake fluids are highly hydroscopic, means they want water molecules.
Stronger with "racing" brake fluids. (The service life does not play a role here, because the fluid is often changed)
This "water absorption" also takes through diffusion, mainly on the brake fluid reservoir (almost without effect) and unfortunately also on the rubber brake hoses, which are located in front of the brake calipers. (That's the bad)
This is not the case with Teflon "Sport" brake lines, e.g. on a much smaller scale. This improves the service life of the brake fluid. Another big advantage is the service life of the hose himself.
These last forever, while "rubber" brake hoses eventually become porous.
Also recommend not choosing the fittings made of stainless steel. Brass fittings are better in aluminum (brake calipers) and steel (brake line). There is no contact corrosion here.
The Renntech price is also 100% above the market price of TÜV-tested, high-quality Teflon brake hoses. With brass Fittings and stainless steel protective braid and plastic coating.
When changing the brake fluid, you should also note that there is brake fluid in the ABS control block. This should also be flushed by actuate this valves (star diagnosis).
Best regards
Stenzel
Last edited by Stenzel-Germany; 12-20-2021 at 02:06 PM.
"When changing the brake fluid, you should also note that there is brake fluid in the ABS control block. This should also be flushed by actuate this valves (star diagnosis)."
12-04-2021, 09:22 AM
