New Calipers and Rotor won't spin


#1

car: 1992 Chevy g20 van 5.7 regular duty brakes



I just installed new wheel bearings, rotor, calipers and brake pads. I have not yet re-connected the brake line.



My problem is that with the new calipers and brake pads mounted the rotor no longer spins freely. Looking down at the pads it seems that possibly the heel end, or the rear end of the inboard pad is dragging. I compressed the piston on the new calipers but still it’s such a tight fit that nothing spins freely. Can anyone offer some advise on what to look for next?


#2

Did you check to make sure the caliper slide pins are free?

Tester


#3

Well, the caliper is free to move on the sleeves, however everything is so tight, there is just not much room for movement. Can you describe how the pins move? They are treaded into the steering knuckle.


#4

Looking everything over very carefully, and I really think that the brake pads are too thick. I’ve read in other forums that some people say to take off the metal anti-squeal backings. Is this ok? That would probably get me the clearance that I’d need.


#5

How freely does the rotors move without the Calipers?? Sure you didn’t tighten down the bolt that holds the bearing in too tight. It doesn’t get cranked down…just a little beyond hand tight.


#6

Nope, I tightened down to compress bearings as described in my shop manual and then loosened to just a tad less than finger tight for the cotter pin. Rotor spins nicely without pads.


#7

Once in a while I encounter the same situation, particularly if I get the parts from AutoZone or Advance. Leave any anti-squeal feature in place or you’ll be reminded that you removed them every time you hit the brakes. Best thing to do is to put each pad in a vise horizontally and carefully sand it down with a belt sander with a medium grit belt in it (parallel to the long dimension of the pad). That keeps it pretty flat and even. Don’t forget to maintain a bevel on the leading edges of the pads. After doing this, everything fits. Next time, get your parts at someplace like NAPA and they’ll fit the first time.


#8

I’ve run into this a few times. The new caliper piston doesn’t fully retract into the bore so it won’t go over the new rotor. Compare it to the side that does mount OK, you might see that the piston isn’t as far into the bore as needed.