When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Rear Brake Caliper rubbing rotor after Axle swap. Is the 3.23 a GM 7.5 or 7.625" Axle
Seems I have a on going problem ever since my rear wheel bears in the axels trashed the stock axels. Back in 2014 I put in some Ten Factory MG22104 - Motive Gear Ten Factory Axle Shafts. At the time I did not notice there were actually two sizes for the Camaro. Further research today it shows there is a GM 7.6" or 7.625" axel. My car has 3.23 stock gears and have no clue if its 7.6" or 7.625" which is the cause of the caliper rubbing the rear rotors. My original thought was my rear brake pads were low but after swapping out with newer slotted/cross drilled rotors and pads earlier this year I noticed that there is very little clearance between the rotor and the rear caliper. I do hear a grinding/scratching noise when making turns but straight line driving it doesnt rub. Should I just shim the caliper for the added clearance? Anyone know if my MG22104 is for the 3.23 geared rear axle? Thanks!
Re: Rear Brake Caliper rubbing rotor after Axel swap. Is the 3.23 a GM 7.6 or 7.625"
Searched the forum like mad. Seem like this is the closest match. Either grind the brake caliper or shim between the caliper and bracket to move caliper outwards.
Re: Rear Brake Caliper rubbing rotor after Axel swap. Is the 3.23 a GM 7.6 or 7.625"
The 10-bolt case accepts both a 7.5" or a 7.625" diameter ring gear. They are interchangeable. The 4th Gens are 7.625", but it really makes no difference. Doesn't affect the carrier, axles, bearings, etc.. Never heard of a 7.6" gear, unless someone just didn't bother to fully type 7.625". Generally it's shown as 7.5/7.625".
If and when any work was done on the rear brakes, were the guide pins replaced, or at least rust-free and well lubricated?
When you installed the new axles, did you replace the C-clips?
Appears to be the correct axles. As noted, has nothing to do with 7.5" vs. 7.625".
Re: Rear Brake Caliper rubbing rotor after Axel swap. Is the 3.23 a GM 7.6 or 7.625"
Originally Posted by Injuneer
The 10-bolt case accepts both a 7.5" or a 7.625" diameter ring gear. They are interchangeable. The 4th Gens are 7.625", but it really makes no difference. Doesn't affect the carrier, axles, bearings, etc.. Never heard of a 7.6" gear, unless someone just didn't bother to fully type 7.625". Generally it's shown as 7.5/7.625".
If and when any work was done on the rear brakes, were the guide pins replaced, or at least rust-free and well lubricated?
When you installed the new axles, did you replace the C-clips?
Appears to be the correct axles. As noted, has nothing to do with 7.5" vs. 7.625".
Thanks Injuneer! Glad after all these years your still helping out. The Rear brakes were replaced with factory units a few years back and the recent pad/rotor replacement seemed like everything was still okay. I'll double check if they are lubed but the rubbing is defintely the caliper housing to rotor. I see a distinct rub mark around the rotor.
As for the new axles done in 2014, I have no clue they might have just reused the old C-clips unless the new set came with them. I did go the Ten Factory units back then cause it was a set and came with the wheel bearings. I figured at the time it would be easier for the shop to replace. Their original install of a off-set bearing leaked and I just didnt feel comfortable with that brand after googling it and it seemed pretty common.
I did order a set of Moog caliper shims from Summit so i'll give that a try when they come in. Now that i feel more comfortable that I have the correct axles i'll start checking to see if there is any play in the hub.
Re: Rear Brake Caliper rubbing rotor after Axel swap. Is the 3.23 a GM 7.6 or 7.625"
Here's some photos of the driver side rear caliper and rotor. Seems like there is minimal clearance. How much of a gap from caliper to rotor is there suppose to be? Driver side rear. Looks like the clearance is minimal. Rubbing rings around rotor Driver side rear. Hardly any clearance.
Re: Rear Brake Caliper rubbing rotor after Axel swap. Is the 3.23 a GM 7.6 or 7.625"
The part that puzzles me is how the contact between the rotor and the caliper bracket (the part that holds the pads, not the finned main body of the caliper) is even possible. Seems like the brake pad should be thick enough to prevent the rotor from contacting the bracket the brake pads are mounted in. Saw this identical problem in a thread on Firebird Nation recently, but the original poster has not come back in about 2 weeks, probably because I was the only person that tried to help him, and I didn't really have an answer. Maybe the rotor starting too close to the bracket to begin with is causing the bracket to deform. The shim would possible help that. Just a guess at this point.
Are you sure the pads are correctly mounted in the bracket (actually, part #17 in the factory service manual diagram - "BRACKET, REAR BRAKE CALIPER ANCHOR"). Are the pads wearing evenly "front to back"? Is the pad worn more at the end where the rotor is rubbing, producing a wedge shaped pad rather than a uniform thickness pad?
There are dimensions given in the factory service manual, for the use of the shim you are looking at. See page 4B-26. in Part 1 of 2. The rear axle assembly (Section 4) and the brakes (Section 5) are both in Part 1.
Re: Rear Brake Caliper rubbing rotor after Axle swap. Is the 3.23 a GM 7.5 or 7.625"
I have/had a similar problem with my drivers side rear also. It is the caliper bracket that is rubbing and not the caliper itself. I used a washer between the caliper bracket and mounting hub to push the caliper outward a little bit. This provides some more clearance between the caliper and outside of the rotor.
I just used the largest diameter washers that would fit in the space available. I don't know the thickness of the washer that I used, but I just tried different ones until it gave me enough clearance. They have been on for three years and about 5000 miles with no issues.
Re: Rear Brake Caliper rubbing rotor after Axle swap. Is the 3.23 a GM 7.5 or 7.625"
Originally Posted by 94_6speedZ
I have/had a similar problem with my drivers side rear also. It is the caliper bracket that is rubbing and not the caliper itself. I used a washer between the caliper bracket and mounting hub to push the caliper outward a little bit. This provides some more clearance between the caliper and outside of the rotor.
I just used the largest diameter washers that would fit in the space available. I don't know the thickness of the washer that I used, but I just tried different ones until it gave me enough clearance. They have been on for three years and about 5000 miles with no issues.
The shims you ordered should work.
-Greg
Thanks Greg! I'll follow up in a few weeks after the Moog caliper shims come in and I find some time to get the car on jacks.
Re: Rear Brake Caliper rubbing rotor after Axle swap. Is the 3.23 a GM 7.5 or 7.625"
The Moog shims came in but opt'd to not use them cause they were made of flimsy plastic. I decided to pick up some M12 washers from the local hardware store for this project. The original clearance from the rotor to the rear caliper bracket was less than 0.022. After putting in the shim i got back about 0.1+ in clearance. Anyone know what the stock clearance is suppose to be? Im still not sure if my brake caliper rubbing is due to the Ten Factory axle upgrades or these slotted rotors that I recently purchased but I do have a hunch its the new axles. My previous power slot rotors never rubbed on the stock axles but I do recall i heard rubbing after the axles were upgraded and thought it was my rear pads needing replacement. Hence the new pads and Slotted/Cross drilled rotors. I'll report back in a few days to see if this fixed it as I didnt have time to test drive it.
Before washer shim on caliper - less than 0.022 clearance. Rubs when making turns. Clearance much better after installing washer shim. 0.101+ Worth of clearance now. Before washer... After washer... M12 High Strength Flat Washer - Perfect fit with bolt head. M12 flat washer installed between caliper. Ordered these MOOG from Summit and waiting 2 months for it to ship. Doesn't seem to be what I thought I was buying. Cheapy plastic shims. Opt'd to go with metal washer instead. Wasted $40 bucks and 2 months waiting for this to come in.
Re: Rear Brake Caliper rubbing rotor after Axle swap. Is the 3.23 a GM 7.5 or 7.625"
Closing out this issue. After 3 days of driving the car to work it seems the issue is resolved. If anyone has this caliper rubbing issue go out to the hardware store and grab some M12 flat washers.
10-06-2018, 03:29 AM
Rear Brake Caliper rubbing rotor after Axle swap. Is the 3.23 a GM 7.5 or 7.625" Axle
Re: Rear Brake Caliper rubbing rotor after Axel swap. Is the 3.23 a GM 7.6 or 7.625"
The Rear brakes were replaced with factory units a few years back and the recent pad/rotor replacement seemed like everything was still okay. I'll double check if they are lubed but the rubbing is defintely the caliper housing to rotor. I see a distinct rub mark around the rotor.
Re: Rear Brake Caliper rubbing rotor after Axel swap. Is the 3.23 a GM 7.6 or 7.625"
