I have an GM 7.625 rearend with open carrier. I also have a supposed limited slip carrier the guy gave me that I am not sure what it is? It has helical cut gears inside, see pictures. Any help to let me know exactly what this is? Ignore the old ring gear that is on it now, I am curious what this is since it looks way different than the usual limited slip springs and clutches I am familiar with. Carrier does have stamping numbers 9022 02500513 on it, but search didn't help with that. Should I consider swapping this carrier into the rearend, or just get a lunchbox locker for the rearend? Am I missing a cross pin or similar, as it has the recess for the axle c-clips in the side axle gears; but this is all I have and seems that it needs something to lock in the c-clips. Thanks for the help!
That sure looks like a TrueTrac. https://www.eaton.com/us/en-us/catalog/differentials/eaton-detroit-truetrac-differential.html
Keep that carrier it is a "Torsen" [from TORque SENsing] they are an amazing rear-end. I have one in my Road-Race Mustang and they are terrific for "turning in" at corners , at will bias the torque on throttle exit. In drag racing, throw it out and use a spool because extreme torque will split them because of end loads from the worm gears [500+hp 8000 rpm launches with slicks and 5:1 gears] They work on the principles of friction in the worm gears [which only transfer torque 1-way] The axles drive the worm gears NOT the carrier/crown-wheel. And the axles are geared together "back-to-back" so they can differentiate between them.[like an open diff] When torque is applied from the crown-wheel the friction of the worm gears will lock up proportionately [equilibrium between axle torque vs crown wheel torque] If you jack the wheels off the ground and spin them, it is exactly the same as an open rear [driving is the same] If you "floored it" mid corner, it will bite enough to cause understeer.[like a Detroit Locker] Torsen's are quiet and not violent like the crude Detroit Locker.
Yes, you are missing parts. There is a pin bolt that goes through the carrier. You can see the hole where the cross shaft on a conventional rear end would be on your diff. And then that goes through thrust blocks that keeps the axles from coming together and keeps the C clips in place so yes you are missing two pieces and the bolt.
Thanks to all for the info, and especially badshifter for the picture of the missing pieces. I'll try contacting the mfr to see if I can get those pieces. I figured something had to hold the axles in place. This would only be used behind approx 300 hp. I wouldn't use this 7.625 rearend with any more power level. But with this carrier it seems a good street choice.
just a note. If you are using a 3.42 or higher ratio , you can use the 1 piece block [which is cheaper] lower ratios [4.1, 3.73, 3.55] need the 2 piece block so they can slip in behind the crown wheel teeth You can get these rear ends to handle 400 hp [in a drag racing situation] but it will cost $$$ Also if you're playing with a GM corporate 10 bolt [3rd-4th Gen Camaro] and want to narrow it! Early Ford Ranger Axles are the 'go-to' [same spline] Because these axles are C-clip they have a full circle flange which makes it easier to re-drill to a different PCD If you are considering narrowing your rear end, consider welding Ford axle-ends to the housing and eliminate the C-clips altogether ,then you can use the cheap 1-piece thrust block with lower ratios [it gets****embled before the crown wheel is installed]
Kerry, thanks for that info, but I am definitely not going to narrow this rearend or contemplate 400 hp. I would use a stronger rearend to start with instead of the small 7.625 rear. Like 9-inch or 8.8, although those have the bolt pattern issue. 7.625 S-10 rearend is in the vehicle and the only question is whether to use this Torsen/True Trac style carrier. It currently has 4.11 gears (I need to verify that, seems accurate from driving), so it would need the 2 piece blocks.
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