Mystery: Z36Powerstop rear brakes excessive inner pad wear after only 4k miles

[OneofFew]

I replaced the entire rear brake set up with z36 Powerstop parts.
Drilled and slotted rotors, calipers and brackets, pads and hardware including drag reduction clips.

I noticed a squeaking noise on the right rear a few days ago, so I decided to check. I found that the inner pad was worn halfway down while the outer was just broken in. Uneven wear on the insides of the rotors that line up with the holes. I found no binding in the caliper slides. anti-seize was applied. I did feel that the pads were a bit tight on the caliper bracket. I only disassembled the right side, but the left side is showing odd wear on the inner side of the rotor also, so I expect similar pad wear.

I double checked my parts list and noticed that I had ordered:

POWER STOP Z36834 [Brake Pad] Severe Duty Truck & Tow; Includes Hardware and Brake Lube Info
FitsRear; 4WD; OE Ceramic - Limited Slip Axle
OrRear; RWD; OE Ceramic

while my vehicle has no limited slip rear axle. I see another Brake pad kit listed for the vehicle for the non limited slip axle:

POWER STOP Z36792 Severe Duty Truck & Tow; Includes Hardware and Brake Lube Info
Rear; 4WD; OE Ceramic - Except Limited Slip Axle

So the question becomes whether there is really a difference in the brake pads from limited slip axle to non limited slip? Or is the difference only in the caliper? 1 versus 2 piston? Could I have ordered the pads for the 1 piston and they fit in my 2 piston calipers??? My old calipers were 2 piston, same as the new ones, but the rotors that were on there were much thinner and were cracked. I assumed that someone had put 2wd rotors on in the past by mistake.

Might there be a difference in the brake hardware kit between those 2 axles?
I have the 3:73 on a 2001 Tahoe 4x4.

 

[Scottydoggs]

if your caliper pistons slide back in with easy, with a C clamp of course, no fighting to push em back in the caliper should be ok.

now you said tight pads, as in the caliper bracket? ive had pads be way to tight, ether the tab at the end is to wide or to long. so ive taken a angle grinder and ground the ends down some till they fit snug, not tight, so they can move as needed.

 

[OneofFew]

That may be the solution, but I would not expect premium pads to be out of spec. But then again, we are living in the Made in China era.

 

[Scottydoggs]

ive had lots of good pads not fit 100% right sadly. on most its like the paint is too thick.

 

[SnowDrifter]

Inner pad wear sounds like a sticking caliper slide tbh. Piston applies from inside, caliper slides towards inside, applying outer pad too.

If the caliper doesn't slide, caliper doesn't slide and you're applying with only inner pad

Did you use anti seize on the caliper slides? Don't do that. It causes them to bind.

How tight are your pads? They should be fairly snug but still movable if ya push 'em with your finger

 

[OneofFew]

Inner pad wear sounds like a sticking caliper slide tbh. Piston applies from inside, caliper slides towards inside, applying outer pad too.

If the caliper doesn't slide, caliper doesn't slide and you're applying with only inner pad

Did you use anti seize on the caliper slides? Don't do that. It causes them to bind.

How tight are your pads? They should be fairly snug but still movable if ya push 'em with your finger

I put anti seize only on the wear points between the pads and the caliper brackets. The caliper pins were pre- lubed from factory (new powerstop 2 piston). I agree that inner pad wear tends to be sticking caliper pins, we have all seen this 100 times, but these are very well lubed. The only thing I do see is limited movement due to the slide boot only allowing about 1/4inch movement and a pad that sits pretty tight in the bracket. I am really wondering if there is a difference between the pads for a limited slip axle and a dual piston set up. Notice in the parts list I have dual piston calipers, but the pads do not list an option for dual piston, only for 4x4 and limited slip axle or 2wd and non limited slip axle.

POWER STOP S4764 (Performance (Improved Stopping Power)) Performance Red Powder Coated; Includes Hardware Info
FitsRear; RWD
OrRear; 4WD; With Dual Piston Rear Calipers

x2

POWER STOP Z36834 [Brake Pad] Severe Duty Truck & Tow; Includes Hardware and Brake Lube Info
FitsRear; 4WD; OE Ceramic - Limited Slip Axle
OrRear; RWD; OE Ceramic




POWER STOP PBK008 [Disc Brake Hardware Kit] Info




1

POWER STOP AR8645XL [Rotor] Extreme Performance Drilled and Slotted; Rear Left Info




1

POWER STOP AR8645XR [Rotor] Extreme Performance Drilled and Slotted; Rear Right Info

 

[OneofFew]

WHen I say the pads are tight in the bracket- I have to pry them out with a screw driver. This is why I am wondering if I have the wrong pad.

 

[Scottydoggs]

WHen I say the pads are tight in the bracket- I have to pry them out with a screw driver. This is why I am wondering if I have the wrong pad.

and this is why i say grind the pad ends down till they fit right. you own em already, go for it.

 

[OneofFew]

if your caliper pistons slide back in with easy, with a C clamp of course, no fighting to push em back in the caliper should be ok.

now you said tight pads, as in the caliper bracket? ive had pads be way to tight, ether the tab at the end is to wide or to long. so ive taken a angle grinder and ground the ends down some till they fit snug, not tight, so they can move as needed.

That is what I just did. The pads were definitely too tight in there and dragging despite the added drag reduction clips. Now those clips can actually push the pads off the rotors. Test drive felt good. We shall see in a few K miles, but this story disappoints me in the Powerstop z36 pads. 500 mile warranty is silly for a $36 set of pads and the don't even fit well. I will replace them with something else next time.

 

[Scottydoggs]

drag reduction clips???? you mean squealers?

when the pads get low those clips hit the rotor and squeal, thats your warning to change the brakes.