I ran into a problem this weekend that was a first for me in my 40+ years of DIY auto repairs. I was wondering if anyone has any insight.

My daughter's 98 Blazer needed new rear pads, so I got them and new rotors. I checked the FSM to make sure no special tools were needed, and to make sure the pistons didn't need to be screwed back in to make room for the new pads (like on Saturns).

Everything went smoothly, except neither of the pistons could be pushed far enough back into the caliper to make room for the new pads. After I found the problem wth the first, I just went to NAPA and got two reman calipers (nice units with adapter, slide pins and all hardware for $38 per side) and used them to get around the problem. ( We were visiting relatives a few hundred miles away, so I just wanted to get the job done right that day.)

I was using a wooden screw clamp that I've used for dozens of disc brake jobs, and even tried opening the bleeder, which let some fluid out but didn't buy me more than a small fraction of an inch of added clearance.

Anyone know what the problem was?

 

I'm having a similar problem with a rear caliper on my 98 Blazer as well. One of my problems is the clamp I'm using is small and I can't get enought leverage to apply much force on the piston (that's what I'm hoping the problem is) I will try a larger clamp tomorrow... I also was wondering if there are any other methods of pushing the piston back into the caliper... otherwise I may have to take a trip to NAPA as well.
In addition to your question, did you bleed only the calipers you replaced or the emtire system?

 

Sometimes, those calipers can be a bi**h to get back in. I've bent the screw shafts, on several of those 4"?? clamps, thru the years. I've got a huge clamp, that I use now, to shove that piston back in there.

 

Only once did I have a problem like what you are describing, but it was on a '76 Camaro that had sat for about 5 months. Rust was the problem in my situation, though. I doubt that is any help for you, though.

 

Actually that was helpful, the Blazer has been sitting for almost a year… In my case, I probably should replace the calipers to avoid future problems!?
Thank you.

 

on my 2002 the pistons went back in no problem, but i found a reloading tool cheaper than a big enough c clamp so i got that...
http://www.canadiantire.ca/AST/brows...2BSpreader.jsp

now that i look at their website there are a few other kits that are good that i would rather..but i got this when it was on sale and used canadian tire money...i think it ended up costing me $5-7

my problem is my back calapers are dragging...i changed the pads no problem but when i hit the brakes they dont release all the way...im sending my rotors to be machined and im going to buy rebuilt calapers and swap them out...its just less of a headache this way...i dont feel like playin around with them too much.

 

This sounds like the slide pins are catching/frozen. Very common and an easy fix. Just pull them, clean them and lube them.

 

what pins are you refering to? the bolts that hold the caliper on?
is it possible to overtighten them which would cause this? i put them on tight but i dont think they are too tight...is there a torque spec?