Posi Differential Info

[gadget73]

Chevys are odd, they don't always have a swappable carrier like the Ford 8.8. In some cases you need to change the entire axle to get a posi rear. Prob should double check that on a GM forum but I'd bet swapping the entire rear would be the least work.

[88Vic]

Swapping the entire rear sounds like a good idea to me. I was also thinking of finding a rear with a posi 4.10 and discs from a 99+ truck. I'll check the Chevy forums to see what will and won't fit.

[ss_mini14]

how can you tell if your trac-lok is bad? a couple weeks ago i had the rear jacked up and decided to spin the tires. there was some resistance but i could easily grab one tire and turn it while the other spun in the opposite direction. maybe mine is ready for a rebuild...

[gadget73]

it spun in an opposite direction? thats usually what an open end rear does. If you can stop one tire while turning the other by hand, its dead. One-wheel peels would also be a sign its tired.

[DuceAnAHalf]

it spun in an opposite direction? thats usually what an open end rear does. If you can stop one tire while turning the other by hand, its dead. One-wheel peels would also be a sign its tired.

my trac-lok does that even when it was new. thats cause i diid not reinstall the "S" spring so when one or both wheels are off the ground it acts like an open rear end

[gadget73]

pardon me for being stupid but what would the point of that be ?

[mrltd]

All the S spring does is add preload. When TQ is applied through the pinion it acts like the limited slip. Gotta remember it's supposed to slip whn power isn't applied. Many road racers don't use the s spring.

[DuceAnAHalf]

i didnt put it in because i tried for a while to install it and then gave up

[ss_mini14]

it spun in an opposite direction? thats usually what an open end rear does. If you can stop one tire while turning the other by hand, its dead. One-wheel peels would also be a sign its tired.

it did spin in the oppotite direction but with some resistance like a brake was dragging. it took some muscle to get the tires to move. also it was in park so the driveshaft was unable to move.

[Mercracer]

Chevys are odd, they don't always have a swappable carrier like the Ford 8.8. In some cases you need to change the entire axle to get a posi rear. Prob should double check that on a GM forum but I'd bet swapping the entire rear would be the least work.

Please give me an example of a single GM axle which you can't swap the carrier out of.....

[Mercracer]

Anyway, assuming that's true, the parts you'd need to get from the boneyard would be the carrier and the ring and pinion set. Tools needed shouldn't be much more than just basic hand tools, though trying to get the pinion nut loose without an impact would undoubtedly be rather interesting. You'd probably be better off trying to buy the stuff already removed (eBay, perhaps).

Then you'd want to get a ring and pinion installation kit, which should come with outer axle bearings, carrier bearings, pinion bearings, carrier shims, pinion shims, crush sleeve, axle seals, and a pinion nut..

You may be able to harvest the old one with "basic" hand tools, but you are going to need more than that to put it together in your housing.....

[Nathan in MI]

You may be able to harvest the old one with "basic" hand tools, but you are going to need more than that to put it together in your housing.....

Well, yeah, that's what I meant, based on this:

And what tools are needed to get the necessary parts from a junkyard truck?

Apologies if that wasn't clear.

[88Vic]

After checking a Chevy forum, they told me that buying a new set of gears/diff was worth the money and that since junkyard parts are unknown that new parts are the safest best as far as reliability. I definitely don't have the tools at home to do the install and by the time I save the money for the gears I won't have the shop at school so i'll probably have to get a shop to install the gears for me

[1987cp]

:bump: Seemed time to resurrect this for updating. Possibly it should be cleaned up and split into a separate sticky?

Anyway. If I understood a recent comment of Mike's in a differential thread, TrueTracs rely on a wheel having a certain minimal amount of traction available in order to transmit torque to it. He mentioned attempting to move a TrueTrac-equipped vehicle in some snow and finding it impossible! This would seem to suggest that a Detroit TrueTrac isn't a good choice for those of us who live in areas where it, like, snows and stuff.

Also, the thread's OP mentioned the existence of a product I'd been previously unaware of called the Powertrax No-Slip Traction System, which the manufacturer claims to be a truly street-friendly locking differential. The idea is that while a conventional limited slip, including a Powertrax Lock-Rite, is taken around a corner, the outer wheel is allowed to freewheel in order to complete the corner. Supposedly the No-Slip instead decouples the inner wheel. Some guy on a 4x4 board claimed it to have been extremely predictable and controllable during testing in a snowy parking lot.