Spare Tire Recall

mrcolieman · May 16, 2023

GETGONE said:
Difference in diameter from one side of the rear axle to the other can cause differential damage. I bought an Avalanche and didn't realize it had two different size tires on the rear axle a week later when I had to put new brake pads on. I bought the correct size and put it on as soon as i could. I don't know how long it was on there but the diff blew up/locked up not long after. If you have to run with two different diameters, put the unequal size on the front and don't run it in 4wd.

Exactly!

. Our G80s are designed to mechanically lock up when one wheel is spinning faster than the other, and on pavement it will cause damage to the unit as it constantly locks/unlocks. In sand, dirt, snow etc. when the wheels can slip on the surface it's not such a big deal. Short video for anyone who wants to geek out with me on how they work! and a pic of the one I rebuilt out of my 05 suburban...I dropped and shattered the cast iron ring gear shim and had to make up the difference with the whole pack of provided shims to get the pattern right

. Worked great for another 40k miles!

GETGONE · May 16, 2023

The carnage from my Avalanche.

mrcolieman · May 16, 2023

GETGONE said:
The carnage from my Avalanche.

OOOOF! i don't think JB Weld can fix that...

Gangly · May 16, 2023

HammerBoss said:
You do know that the only tire that fits on a 20" dia. wheel is a 20" dia. tire right?

When you think the issue is something that simple, and that you are the only one able to figure it out, you probably need to step back and make sure that you aren't the one who is misunderstaning or missing information. You are obviously confused, so let me help you out.

The issue isn't the diameter of the wheel but the diameter of the tire. More specifically, the OUTSIDE diameter of the tire. All outside diameters of the tires, ie 33" or 34", etc. have to match up or your axles will be turning at different rates creating all sorts of issues with lockers and the 4WD system when in use. However, you can run 4 different sized wheels at all four courners, for instance an 18", 19", 20", and 21" inch wheel at all 4 corners, and it wouldn't be an issue (as far as the divetrain system is concerned) as long as the OUTSIDE diameters of the TIRES are all the same. Again, the recall is associated with mismatched OUTER tire diameters and has nothing to do with the spare wheel being a different wheel size than the 4 wheels mounted at the four corners from the factory. .