brakes

[andihaz 0]

Thought i'd give my brakes a test yesterday, as the road was a bit wet, and have just got some new tyres (F1's front and toyos rear), was on a long straight on a quiet country road. When i braked hard the back left locked up and caused the car to vear to the right, as if the back end was stepping out. Thought it might have been due to some oil or grease on that bit of road, but everytime i tried it happened just the same.

 

Anyone with any experience of this, or ideas on what could be causing this?

 

I guess it won't have anything to do with the bias valve, as surely that would make both rears lock up not just the n/s. i jacked the car up when i got home, and apart from the bearing being a bit loose, their seemed nothing wrong, also checked the tyre pressures and they were all fine.

 

In all my previous cars, it would always be the fronts that locked up first, as they take about 80% of the braking force i think.

 

So any ideas would be greatly appreciated.

Am thinking about taking it to a garage and using their brake force testing rollers and see whats going on front and rears.

[dinkus 10]

It could be that you have a ceased or dying calliper at the rear (quite common) or it could be that you drove over some road markings or gravel which have less grip.

 

If you're braking properly then it should be the rears that lock first.

 

 

The brakes are bigger at the front because they're designed to stop the engine as well as the car, so if you put the clutch down when you're braking hard then you'll lock the front wheels, which will slow you less quickly than keeping the clutch engaged.

[andihaz 0]

So your saying that the one that is dying would be the one that didnt lock?

Would the handbrake operation be affected by this? as it is pretty useless at the mo (even more then usual) but i havent tried to see what side thats on, i think that i will go get some readings off a brake force meter at a garage.

Cheers

[dinkus 10]

Yeah, the handbrake operation will be affected too, so if your handbrake takes a very long way to work, then it's probably one (or both) of the rear callipers that's dying.

 

If you do need to replace the callipers, then the Mk4 Golf ones are a good option instead. You'll need some adapter flexi-hoses to fit them, but they're alloy and a much better design, so shouldn't cease on you again.

 

You can get the callipers and hoses from C&R for about £200 all in, but the hoses are about £20 and the callipers can be had second hand for not too much money.

 

Although the standard Corrado pads will work, the best pads to use with the Mk4 callipers are the late Mk3 GTI ones. Don't ask why, cos nobody seems to understand, but they are :D