I bought the Centric Zinc plated Rotors and Posi-Quiet pads... did the install this weekend, haven't had a chance to give it a shakedown yet (will do the bedding procedure on the stoptech site, after zinc plating wears off from light driving). I have a few quick questions.
Is it normal to have varying weights between the rotors? For example, for the front rotors, one weighed 19.6 lbs, the other 19.8 lbs. For the rears, one weighed 26.0 lbs, the other 26.2 lbs. Unfortunately the only scale I had available (electronic bathroom) measured by .2 increments (but these means a variance of at least .1). I measured three times each rotor, to make sure. So I'm guessing they're probably off by about .1 - .3 lbs each (no big deal?). I put the lighter rotors on the driver side, since my fat butt will always be in the car.
The other question is on the parking brake - the two rear rotors varied some for the parking brake shoe area (measured with calipers)... one side 7.43050", the other 7.48155" (normal?). The manual had no specs I could find for this measurement. The rotor with the smaller diameter for the parking brake shoe scuffed some of the materials off the parking brake shoe when I slide it on (didn't realize it was hanging it up, before I got to adjust it).
I'm paranoid, thought about replacing the parking brake shoe I scuffed up... and in the service manual, says to remove the wheel hub to do so. Any way around that - to replace the parking brake shoe with only the rotor removed? Removing the wheel hub looks to be a pain.
Thanks in advance for the feedback. I hope to give a review of the Centric/Posi-Quiet combo after I get them broken in.
It seems weird to me that the rotors weigh in differently, thoughts guys? I don't know if that is common or not, just seems like they should be closer than that-
The rotor with the smaller diameter for the parking brake shoe scuffed some of the materials off the parking brake shoe when I slide it on (didn't realize it was hanging it up, before I got to adjust it).
I'm paranoid, thought about replacing the parking brake shoe I scuffed up... and in the service manual, says to remove the wheel hub to do so. Any way around that - to replace the parking brake shoe with only the rotor removed? Removing the wheel hub looks to be a pain.
I wouldn't worry about the parking brake shoe being scuffed. You can chew them up pretty badly and they still work. GM uses the same style design on quite a few vehicles including trucks. When you pull the rotor off from a truck that has been run for 3 winters in salt and sand there is no way you aren't going to badly score the parking brake shoe. The rust and dirt build up is so large it is almost impossible to get the rotor off the parking brake shoes. When I replaced the parking brake shoes on my Tahoe the instructions said the rear axle had to be pulled, which, would mean opening the diff and removing a C Clamp to free the axle. Not something I was going to do. The only reason that I can see for that is it is a royal PIA to remove the old shoes and install new ones over the hub flange. I did it but it took some work.
Thanks guys, for the info. After some digging around it does seem many GM vehicles use the same parking brake shoe (PBR W0133-1616166). Maybe I'll pass on swapping the shoe, since it seems a chore and I don't want to remove the hub.
I have light pulsation on the new rotors with light to moderate pedal application (noticeable at low speeds) - only driven about 15 - 20 miles so far with the intent to "season" the rotors and scrub the Zinc plating before doing any bedding bedding. My understanding of bedding is to transfer material, and I don't expect it to affect the pulsation I'm feeling (haven't narrowed it down to a specific rotor yet - my GF said she wouldn't have noticed unless I said something - but I was expecting silky smooth).
I'm going to check LRO when some parts arrive, as I couldn't do it according to the service manual (I did not have the conical washers - J-45101-100 - so I did not torque the lugs down to spec checking LRO when first assembling). Doing the lugs hand tight, they were all .003" or less (spec is .002"). These are brand new Centric rotors, so I'm expecting them to be pretty true - since they weren't torqued when measuring... or the initial Zinc plating... that might be the issue?.
Worst case I'll toss the original rotors back on, say front set, to narrow in on where pulsation may be coming from. Everything was smooth before - this effort was to reduce some brake dust and have rotors that didn't have as much a rust issue.
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Parking Brake & Rotor Weight Question
