Posi Question

[dmsteele92831]

If I have a 12 bolt 3.07 rear end will this posi unit work on my truck?

12 BOLT 8.875 CHEVY 30 SPLINE TRUCK POSI / LOCKER

[71chevylowrider]

if this is an eaton style posi then it needs to be a series 3 carrier's go from 3.07 to 3.73, series 4 carriers start at 3.73 & go up to 4.56 these are limeted slip units that we still refer to as posi, but a locker is locked all the time & wouldn't be adviseable for street use, better get some pictures of what their talking about, also if you find another one make sure it's a truck carrier cause one for a car is different & won't fit right in a truck housing.

[dmsteele92831]

Here's a link to the auction, and my truck will be for street use

http://cgi.ebay.com/ebaymotors/ws/eB...9771798&rd=1,1

[71chevylowrider]

stay away from it! Those are the ones that have lots of little pieces that always break

[71chevylowrider]

This is the kind you want, this is an eaton series 3 carrier. I'll find some other pictures that show it from the side view so you can see the big difference.

[dmsteele92831]

Thank you! That works on the 3.07 rear end?

[71chevylowrider]

here's what they look like on the inside. This is the one you want & the correct part number, you can find them used on ebay also, here's summits listing for it, kind of expensive, I think you can a new one cheaper at drive train specialties if you wanted to buy new.


http://store.summitracing.com/partde...5&autoview=sku

[dmsteele92831]

Nice, thank you much!

[71chevylowrider]

see what I mean price wise?

http://www.drivetrainspecialists.com...ed-slip-1.html

[dmsteele92831]

Nice, what would a mechanic typically charge to install one of these?

[kevncar]

I thought I heard somebody on here say that if you like to have a little fun and do burnouts and stuff, that you can burn up eaton??? And that you were better off going with the detroit locker. The lockers aren't street worthy? I am looking into doing this upgrade sometime in the near (hopefully) future and had originally thought of the Tru-trac, then people were saying so with the eaton for servicability, and then I got that becuase I was running a big-block and like the smell of melted rubber, that a locker was the only way to go. Help straighten me out guys.

thanks

[71chevylowrider]

sorry, the original ad he posted had the word locker in it, which made me think they were referring to one of those locker units that lock both axles for drag racing, their fine for that, but would suck for the road, imagine trying to make turns in the rain? I guess some are called spoolers, but you never know what "they" (the seller) might have meant by the term "Locker" the detroit locker is a good unit, it seems to be more popular with the 4X4 guys, & I think they make a little clicking noise when you make turns, (it's the internal clutch's engaging/dis-engaging) it doesn't bother some, I wouldn't want to hear it, but again in a 4X4 it wouldn't be too big of deal. I beleive the eaton is plenty strong & is the normal replacement in these older Gm 12 bolt truck housings, & is quiet when it engages. It is a good discussion topic though, alot of guys here have eatons, & I'm sure there's quite a few that have Detroit Lockers, you could put up a post & ask about the 2 units to help you make the best choice for your purpose. I do know that the one in the ad he was looking at is the one that has alot of problems, I think their called a gov lock or something along those lines.