hey all, how ya doin. so today i replaced the rotor and pads on my back drivers side. I have done brakes before but this time i could not get the caliper to retract to get pads back in. I got the pads in and reassembled it. When I took it for a drive it smoked like crazy on that wheel and smelled bad. Does this mean the caliper is seized? Is there any way to fix this myself? Or what do i need to do? I am without a vehicle now. Please help. Thank you.

 

Sounds like you may need to rebuild your caliper. Is the caliper rusted at all? Another thing if you have the old pads lying around still take and old pad and a clamp and try to press the piston in, if it doesn't budge at all then it needs to be taken off and apart. [sm=signs003.gif]

 

It sounds like the caliper is siezed. Did you open the bleeder screw as you tried to push the caliper piston back in?

 

Mark,

I also had this problem once. What happens is the piston in the caliper swells (for lack of a better explanation) The piston isn't the aluminum configuration that is normally seen in a cast iron caliper. I believe that it is of a phenolic or baklite (sp) type construction. An aluminum piston in the caliper would expand at the same rate as the caliper itself due to the heat generated by the brake pads. In order to compensate for this expansion the clearances would have to be excessively large. So large in fact that there is little chance that a seal would survive.(factor in hyd pressure and heat ) The factory uses aluminum calipers for numberous reasons ( not that we need to go into them)
So heres the deal (from my exp) the calipers are NOT rebuildable by the average Joe. To my knowledge there is no rebuild kit avalible, trust me I looked everywhere for 2 wks. You'll have to buy a new one or a rebuild, and to be honest they really don't cost that much. (word of advise here: trying to increase the clearance between the piston and the caliper bore with emery cloth or similer method is an exercise in futility,........been there tried that!)
Next thing, take the original pads with you when you buy new ones. I don't know if there was a mid year change (in my case anyway) but I went thru 3 sets of Duralast (NEVER AGAIN)Same part, number same box for all, and they were all too thick. The metal backing was the same but the pad material was too thick.(even with the piston fully retracted in the caliper there was not enough clearance between the pads and therotor (causes a slight drag between them, that's why you got the smoke and the smell) I finally went back to AC Delco's and had no problems whatsoever.If you want to use another brand that's fine, just match them up with the originals.

Hope this answers you questions, if you need futher info just ask.

Good luck

Gator

 

First thing I would recommend is to open the bleeder and see if the caliper will go back in as Rob has suggested. If it does, then I would look into replacing the rubber brake line. I have seen these lines swell on the inside, cutting off fluid pressure into and out of the line causing a bunch of problems.

If you open the bleeder and nothing comes out when you apply pressure with a C-clamp, then your caliper is froze up. If it were me, I would replace the rubber brake lines at the same time while you've got the system open.

 

UPDATE,
I have located a rear caliper overhaul kit from GM, the part number is 18026037. Unfortunately I cannot tell you what parts are included within this kit.( I'm assuming it includes the piston and all seals needed)
Wish I could have located it when I had to both the rear calipers on mine.

Gator