didn't find any that were trustworthy. i only found one near Berlin that has a great reputation. unfortunately they only work for companies, not private persons 😢
HELP GM 8.5 axle rebuild... Will this run?
- Thread starter FluoFerret
- Start date
didn't find any that were trustworthy. i only found one near Berlin that has a great reputation. unfortunately they only work for companies, not private persons 😢
It looks good... assuming the carrier shims take up the gaps and backlash are good (0.005-0.009"), it is a runner. Let's see what it looks like with pinion shim 0.038" (nominal is 0.037). As good as it looks at 0.041, it should look shallow at 0.038".
Perhaps you shared that one picture because you think it is good and final. In that case it looks good. Of course we would like to see shallow 0.003 so we can have more information
Perhaps you shared that one picture because you think it is good and final. In that case it looks good. Of course we would like to see shallow 0.003 so we can have more information
Monzaz has stated before that rule of thumb is if you can reach in and yank out the carrier with your hands, without a pry bar, it's too loose. If you're bending shims when tapping them in, it's too tight. 64nailhead got it right. Tap in the shims and they should be firm going in without bending and you should be pretty much there.
110% - if you can pull out the carrier with your fingers, then that is not good enough.
When I use a feeler gauge to test for zero lash on the carrier bearings, I found that very thin one like .001" are impossible to squeeze in there. Something stiff enough to not bend like .010" works better. So if you can just barely insert the gauge between the bearing and carrier, you are at zero lash. But you must add that .010' to the total shim thickness. One you have the backlash and tooth contact pattern right, then you add more shim to get the pre-load. IIRC the GM pre-load is .008" more shim. But you add .004" evenly to each side so it doesn't move the carrier in either direction. As 64nailhaed stated, you will take things apart a lot of times to get it right.
We have the multiple shim packs to do this. The factory did the same, but once the shim thickness was decided upon, they selected a cast iron shim that size for both sides. They used a shim installation tool to push them in without breaking them. It is a rare day when I can re-use a factory cast shim. I once converted my 7.5" Malibu rear to a posi. I was able to swap the factory shims from side to side and it worked out perfectly. I was flabbergasted. That same rear is my Bonnewagon right now. Do it right, and it will last.
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I know I got lucky when I rebuilt my 7.5 in my El Camino in college when I blew it and cracked the carrier, I was able to reuse the stock shims, but I also had gotten a stock carrier from another 7.5 to put in it, so that helped.
Hey, it's hard enough to find a good rear end man around here in the USA [that did not come out right]. In Europe you would need a specialty shop that caters to American cars. What European models use rear wheel drive? There 'may' be some American GI clubs that do stuff like that, maybe even willing for hire, being an American car. I still say the OP can do it. He just needs to be educated about the process.
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