I have an old (2007) Jeep liberty, I had my rear brakes redone at the end of January. The calipers, rotors and pads were all replaced by a close friend. I just started having horrific grinding in the rear brakes this week, and it is worsening rapidly, to the point where I’m not driving it now. I’m going to have it addressed tomorrow, but my question is this: do deteriorating shocks and struts cause rapid brake wear like that, or is it more likely a problem with the brake job or parts? I drive very conservatively and don’t ride the brake, I have had no pulling or indication of anything amiss prior to this week when the grinding started. Please be kind, I don’t know a lot about this stuff and Google hasn’t really answered my question about the shocks potentially being a contributing factor.
No. Bad shocks or struts don’t affect the brakes.
And Thank YOU for spelling “brake” correctly instead of “breaks”. Seriously, no snark here. You can’t imagine how many people spell it wrong.
Yes. I’d guess your close friend compressed the caliper pistons and corrosion inside the caliper cause them to bind wearing out the pads quickly. Kills your fuel economy, too.
It may also be and issue where the the center brake hose over the rear axle has internally failed and created a check valve causing the brakes to stay applied. It is easy enough to check. If you take it to a pro for repair, tell them what I told you here so he checks them properly.
Or if your friend wants to check this, drive around a bit getting the engine warm. Stop, and check the rear wheels to see if they are warmer than the fronts. Then, crack a bleed fitting on the rear. If fluid comes squirting out, not just dribbling, the hose has failed. Replace them all, trust me, if one goes, they all follow closely behind.
Thank you for this info!! Spelling generally isn’t my downfall, but mechanical knowledge certainly is. 
I’ll have him read this tomorrow, thanks a lot!
Not a shock problem. I’m no late model Jeep expert but does this model have a set of parking brake shoes? I’m reasonably certain it does. Checking this should be part of a brake job. It’s possible they could have been acceptable 5 months ago and gave up since then.
Use the park brake much? 2WD or 4WD?
No affiliation with this company. Just showing you the items.
OP did say calipers were replaced.
I’d like to know where the replacement parts were purchased.
I’ve seen aftermarket reman calipers bought from a chain store drag fresh out of the box.
Doh, I missed that! Thanks
He bought the parts at auto zone
I have only ever used the parking brake about 3 or 4 times honestly. He did check the parking brake too, and it was apparently OK. It is a 4wd, which I use very frequently as I live in the arctic tundra.
I don’t trust them for much other than fuzzy dice and air fresheners. 
I’ll keep that in mind, where is a better place to buy parts?
So, apparently my inside rear pad was completely wiped out, but the outer pad was barely worn. The caliper wasn’t hung up. Not sure what’s going on with it.
The slides or pins are binding badly.
I’m not a big fan of the national chains. I hear O’Reilly’s is good, but don’ have one convenient to me. I use a couple local chains. Easier to deal with and the people are far more knowledgeable then the high-school kids who work at AutoZone, PepBoys, or Advance Auto.
There are several reasons for this.
Pads are binding due to properly installed or lack of grease.
A crimped brake line.
Not sure what @Ok is eluding to about the parking brake pads. If like the ones on our Toyota’s like he’s suggesting - I don’t understand how the parking brake shoes will affect the grinding noise when you press on the brakes. Two separate systems. And on the vehicles we’ve owned with this setup…those shoes lasted the life of the vehicle. Just use it for holding the vehicle…not for stopping the vehicle…the shoes really never wear out.
My youngest son went through some park brake shoe noise on his Aviator some years ago. Apparently a cable was hanging a bit and at some point a spring gave up. At times during braking there was not a grinding as much as it was an erratic rattle.
He had a shop where he lives look at it and they found nothing wrong with the rear brakes but the noise continued. Eventually someone there figured rear park brakes were the culprit and the problem was solved with new shoes and hardware kit.
Agreed. Park shoes should last the life of the car short of a hanging cable or forgetting to release them.
Thanks for the explanation. I was sure you knew what you were talking about…I’m just a backyard mechanic.