[jayd_2]

I just installed a Blazer 2wd Disc brake rearend on my 2WD S10 frame, I used new rotors and pads with rebuilt calipers. The brakes work great but are getting super hot, the left rear smokes after driving a few miles. It's got alloy wheels and you can barely touch them after driving, it takes over and hour for them to cool down, the rotors have to be even hotter. The front wheels are hot but not near as much as the rears.

I've driven it 2 times for about 5 miles total, followed manufacturers breakin procedure, there's still a little drag when the brakes are disengaged.

The calipers slide freely on the mounting brackets and the braking is great no lockups or pulling. I'm pretty sure most of the heat is from the pads dragging on the rotors when disengaged.

How many miles/stops should it take for the pads to breakin or wear until there's little or no drag when disengaged?

[302 Z28]

IMHO you have some serious issues to correct. With the wheel free of the ground you should be able to rotate it with a little resistance. They should not be getting that hot.

Vince

[timothale]

drum brakes use 10 # residual pressure , disc only need 2# are you running a drum master cyl-combo valve , you need disc disc setup. , how is the e brake adjusted?

[sedanbob]

I would suspect the residual valve if you went from drums to discs. Also inspect the pistons in those calipers to make sure they are smooth and do not have ridges worn into them that would prevent them from retracting after you take your foot off the brake.

[jayd_2]

I did have drum rear with a 10lb valve went to a 2lb. The pistons were in great condition should be working fine. The MC is a corvette style Disc/Disc and I do have a proportioning valve on the rear.

I did not have any issues with the brakes using drum rearend, all that changed was the rearend with disc and the 2lb valve.

After they cooled down I can roll the truck easier by hand than before the last test drive.

Going for another ride now.

[cobalt327]

Originally Posted by jayd_2

I did have drum rear with a 10lb valve went to a 2lb. The pistons were in great condition should be working fine. The MC is a corvette style Disc/Disc and I do have a proportioning valve on the rear.

I did not have any issues with the brakes using drum rearend, all that changed was the rearend with disc and the 2lb valve.

After they cooled down I can roll the truck easier by hand than before the last test drive.

Going for another ride now.

Get rid of all the residual pressure valving to the rear calipers. Be sure the master cylinder doesn't have an integral valve.

[jayd_2]

I found the problem, it was the import caliper rebuild kit, the pistons were sticking. The "O" rings must not be the correct dimensions causing the pistons to stick, yes they were the correct part number. The original phenolic pistons were in great shape as were the caliper bores they should have been fine.

I replaced the calipers with Autozone (Cardone) remans along with their ceramic pads and everything works perfectly. Adding rear disc increased braking power significantly.