I have messed with disc brakes a little, but not a ton. I just put new pads on a car using GM single piston calipers. I noticed one side has quite a bit more drag on it then the other now. The rotors aren't warped or anything though. When on jack stands one wheel spinds easily but the other requires more force and drags alot more. I've driven it and it feels fine, doesn't pull to one side, isn't noisy and still rolls in neutral easily. Should I take the wheel off and caliper, and loosen the bleeder and compress the piston, in case its hanging up on something? Or will it be ok to drive it like it is? I was figureing after a few miles the pads might wear down enough to where it didn't drag like it is. I just didn't want to build up too much heat. I know some drag is normal but it seems like its tighter than I've felt them before. Thanks.
Did you use pad spreaders or anything to push the piston back? If the pads you replaced were pretty thin, the caliper piston's old rest state will be too close with the new meat on there. You should be able to open up the master cylinder cap and push the piston back. If you don't have a spreader tool, a C-clamp works quite nice.
Did you clean the caliper surface where it slides real well. May have a little build up there. Were the old pads worn the same amount side to side. If they were thne you mght drive it for awhile, checking to see if the one side heats uo.
Have you put it up on stands and tried the spin test since you drove it? If not, it is probably fine now. Disc brakes always have a light drag. You probably just had one piston pushed back further than the other, which would correct itself when you applied the brakes.
I did use a c-clamp to push the piston in when I changed the pads. After I drove it around the neighborhood I jacked it up and it felt the same. Think I'll just drive it for a little while and keep an eye on it, to make sure it doesn't get too hot and then recheck it. I think its just because the new pads are so thick. Thanks.
Make sure the caliper moves freely if not clean up the sliders real well. You should be able to move the caliper some with both hands.
Often gunk builds up behind the piston as the brake pads wear down. when you push the piston in for new pads, the piston catches on the gunk, and will not retract like it's supposed to. In it was mine, I would replace, or rebuild the caliper.
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