Are the pistons supposed to be hard to retract when swapping pads on the rear? Thought I would address a loud squeal (usually only when reversing) by using genuine pads instead of what is in there however I can't seem to get one side to retract (using a G-clamp). Should i assume I have a stuck piston? If so, can I just get one rebuilt instead of both? Good new ones are harder to find over here and usually special order so a rebuild is usually cheaper and faster then special order. Thanks

 

Why not rebuild it yourself.... a lot cheaper and a lot more satisfying..
Kits will run you about $25.
http://www.fcpeuro.com/products/volv...s70-v70-270902

But yes you can replace just one...
Have you checked the shoes?

 

brake shoes? They aren't drums.

Ordering parts takes too long. Need it on the road in a couple days so rebuilding locally is the way to go. Sadly buying rebuild kits in NZ for an 850 is a rare thing.

 

I think he meant the shoes for the handbrake - in the centre of the disk.

 

oh right. No, I haven't pulled the rear disc off so I haven't seen the shoe. Just focussing on the piston that doesn't want to retract. Don't know what the shoe would have to do with a stuck piston though.

 

The poster said they were trying to address a squealing issue.

 

fair enough but I'm trying to address the stuck piston. That's what all my questions related to, not the source of the squeal. Plenty of info online about fixing the annoying sound!

 

Sorry that someone tried to address all of your problems?

 

Pointless... but what ever...... Time is obviously an issue, Just buy the cheaper rebuilt caliper, put it on... no more sticky caliper...

and FYI I did answer your question if you fully read my first post.... and I quote "But yes you can replace just one..."

 

I just wanted info on the caliper piston. Thanks for the extra info. There are no rebuilt caliper units available in NZ unless through the dealer which is over $1000 locally. Having a shop rebuild it locally is cheaper and faster then shipping something from overseas. I just wanted to know if the pistons were supposed to be hard to retract.

 

If you only wanted to know if pistons were suppose to be hard to retract, why did you ask if you could replace just one? Also, you know they shouldn't be hard to compress because they should retract on their own when you let your foot off the brake. Using a clamp should be almost effortless.

I usually keep an old pad on the inside af the caliper as I compress it to avoid damaging the piston with the clamp. Hopefully someone can use this info, I'm sure it's just wasted text for you.

 

The best time to check the shoes is when you have the calipers off the rears.

 

Autozone and Oreilly have both started to carry the parking brake shoes ($26) but for the hardware you still need to contact someone Volvo specific like FCP or Volvopartswebstore.

 

use a long pry bar, and have a old pad on the other side of the rotor to keep the other piston from trying to pop out.

15 minutes you should be able to swap pads -- thats both sides.

make sure you don't force it too quickly thats how you ruin calipers also the faster you try to get it back in the harder it is.

 

Can't get any slower than a G/C clamp.

 

It's also a good idea to open the bleeder when you push that caliper piston back in. That way if there is any "crud" sitting inside that caliper it's more likely to get pushed out the bleeder and not get pushed backward up the system and into the ABS unit or master cylinder.

 

Don't forget to grease the caliper slide pins!

 

caliper slide pins? Aren't those only on the front? I thought the pins in the rear are basically just retention pins for the pads/springs and don't require grease? I have new springs and pins anyways.

Brake shoes/springs are in good shape. No worries there.

Brake shop could not get the piston out of the caliper. They actually broke the face of the piston trying to get it out. They just handed it back saying I should find another caliper if I can. He could get a new piston (assuming he could get the old out) however he couldn't source any rebuild kits. Not surprising as I don't think the 850 was sold new in NZ. Mine came from Singapore.

I've found a caliper at the wreckers. Should arrive tomorrow.

 

Because I'm assuming I don't have a stuck piston on both calipers even though I've only removed the side that was causing the squeal. Wanting to know if I have to replace both is just in case its similar to replacing pads in pairs etc. If one caliper is rebuilt and slides very well, just thought it might cause different wear compared to a well worn caliper. I just asked to make sure.

I wanted to know if it was hard to retract on the 850. I haven't had to work on these brakes before. I have an old Super Beetle and I didn't have much trouble retracting those calipers.

No need to get snippy.

 

The point was that you got snippy with someone that was trying to help you. Also any thread in the forum is there to help not only you but others that may read the thread in the future. So the more information written in a thread may help others that read it, especially if they don't understand other things about the system in question.