571 emergency repair
(10 low res pics loading)
NOV 4 2006

Saturday at work, I get a call. It's Flex on his cell and he busted the front non-cryo'd 571 that I set up for him 2 years ago. He was on a waterfall on a "trail" called Over-dose in Florence, AZ. Fortunately, I had a high quality 571 Precision on the shelf. I had him bring it over that night and in about 2 hours he leaves with a good 3rd. Follow this link to see how the build went on that one 2 years ago.

Flex has been running diffs built by me very hard....the rear Precision 571 is cryo-treated and has the stronger chrome-moly axles. The front was a 571 US GEAR....not cryo'd. The front axles are the deluxe Bobby Long 30 spliners. The tires are 40"....4.3L Vortec...TH350 automatic...4.7 transfer case.

Pinion pre-load still ok...

Looking at the coast pattern from 2 years ago, the Precision brand gear just seems to have a sweeter classic painted pattern.


Not much time for extensive pics....Flex still has to re-install this 3rd tonight and do a trail in the morn...if you can call it a trail :) I set pinion pre-load to 10 in/lb.... .075" pinion shim for depth....backlash a little tight at .006" but plenty of room for good lubrication. CBPL holding at 125 ft/lbs. In the pic above, depth is deep by 2 thou. I'm not going to say for sure that that adds to more strength 100% positive.....because I am not positive....but I don't think it will hurt him a bit, in this case.

Coast side....is much closer to the stronger root of the tooth than the coast pattern on the US GEAR from 2 years ago. Flex was running hard on the coast side when he busted.

...making sure that "ring gear deflections" will be at an absolute minimum. Backlash kept tight at .006" but never tighter than that to avoid starving the ring for gear oil.

Putting my new mark next to my old one.

arrr....here ya go Flex. It's not cryo treated but it is an excellent quality gear and it did set-up VERY well. PRECISION gears rule! Have fun! ZUK