Rear Brake lockup

[99cobra]

Has anyone had their rear brakes lock? I was at Gingerman for an event, and twice it felt like my rear brakes locked at the end of a straight leading to "tankslappers".

I have never had this happen before.

Any way to adjust bias?

Recent changes: 315 rear, 295 front, 18 all around, new rear calipers, new pads all around. I can't figure it out. It's

[wtknght1]

Originally Posted by 99cobra

Has anyone had their rear brakes lock? I was at Gingerman for an event, and twice it felt like my rear brakes locked at the end of a straight leading to "tankslappers".

I have never had this happen before.

Any way to adjust bias?

Recent changes: 315 rear, 295 front, 18 all around, new rear calipers, new pads all around. I can't figure it out. It's

No offense, but it's probably poor braking technique. Don't stab the brakes...squeeze them down further as the weight transfers....and make sure you are straight when you hit the brakes. If you are at an angle or slightly turning, that could cause undue drama!! Were you trying to downshift too?

Since you just replaced the rear calipers, that may have something to do with it too...along with your brakes. What are you using?

Generally though, even if you mash the brakes the ABS will kick in and save you. I doubt seriously you have a bias issue and wouldn't recommend fooling with that!

[UstaB-GS549]

Check to make sure you do not have toe-out at rear. That will lead to rear end trying to swap ends.

[99cobra]

Originally Posted by wtknght1

No offense, but it's probably poor braking technique. Don't stab the brakes...squeeze them down further as the weight transfers....and make sure you are straight when you hit the brakes. If you are at an angle or slightly turning, that could cause undue drama!! Were you trying to downshift too?

Since you just replaced the rear calipers, that may have something to do with it too...along with your brakes. What are you using?

Generally though, even if you mash the brakes the ABS will kick in and save you. I doubt seriously you have a bias issue and wouldn't recommend fooling with that!

No offense taken, but I would have expected the ABS to kick in, as you also stated. I am running Cobalts as i always'have. The new calipers could be more effective, that is why i am wondering about bias

[Jaymz]

I doubt that it's the new calipers... Try another set of pads, maybe an old spare set. Maybe the compound is a little different that what you are used to.

[wtknght1]

Originally Posted by 99cobra

No offense taken, but I would have expected the ABS to kick in, as you also stated. I am running Cobalts as i always'have. The new calipers could be more effective, that is why i am wondering about bias

Normally I don't change rear calipers by themselves or one side of the car by itself. I will use new front calipers with old rear ones because I like really, really good front braking power to rotate the car, so my first recommendation is to do what's been mentioned already:

1. Ensure you are braking properly!
2. Change pads and bed in good
3. Replace front calipers to new as well.

If that still doesn't fix it, you may have some bad rear calipers, but I've never seen any that were bad. Just remember to change one thing at a time so you'll know for sure what caused it. Good luck!