ataylors

iTrader: (2)

It seems that most people are saying with a M6 that you have to go 9" and I just cant see that being the case. It seems most of the problems stem from production line building. Just trying to get some insight here.

silver02ws6

iTrader: (2)

With an M6 you can go with whatever rear you want that will hold up to your needs. Its just that the 9" is a very sturdy very proven rear end.

Ryan02SS

iTrader: (3)

From what i've seen at local tracks and from here the weakpoint of the 12 bolts seem to be the Eaton Posi's. Then seem to not like H/C power and high rpm slick dumps. I've not heard of too many spooled 12 bolts having problems doing the above. Hopefully the new Detroit TruTrak is proving to be stronger than the Eaton and should alleviate some 12 bolt problems.

ataylors

iTrader: (2)

thats what I thought.

SSmokin 01

iTrader: (14)

Strange 12 bolt w/3.73's & 33 spline axles.
Spider gears and side gears went in the posi.
Launching @ 4K, 3750 lbs on a 325/50 MT DR.
614 rwhp / 537 rwtq

Replaced with a trutrac. I'll be at a track rental in a couple weeks to test it out.

NXZ

I have a M6 and I trashed 2 moser 12 bolts 33 spline Auburn posi carier. 75 shot of nitrous, stock motor and a slick tire. The tire was what did it

ataylors

iTrader: (2)

how long did that take?

smokeum99ta

iTrader: (15)

I've broke 4 or R&P's, one set of spiders, and twisted a 33 spline axle on a moser 12 bolt.

SSmokin 01

iTrader: (14)

I've had the rear in the car for around 15k miles. Quite a bit of abuse on the street, about 20 track passes at 430 rwhp, 10 or so at 550 rwhp, 4 passes at the current level.

The first 30 passes were on 17" DR's with soft 60'. The last 4 were on 325/50/15 DR's. As soon as it hooked on the last pass it was dead. The ring and pinion were fine. Just the spider and side gears. I blame the posi, not the rear.

chicane

Looks like what you needed was a heat treated 10-17 spider gear kit. The teeth of the pictured gears, failed due to impact loading.... eg. drag racing.

The Eatons available are almost near what Eaton put out stock, some 38+ years ago..... but the difference was the heat treat of the 10-17 gears and solid clutches.

Out of the several hundred 12 bolts I have built, I have seen that the older parts are much better. But what you as the end consumer know (or are being told) is that you can just drop this into your ride and it will live. Even some 38+ years ago, when dealing with roughly the same power levels, the failures that I keep hearing about are from the newer re-pop Eatons.

I wouldnt have sold you a stock Eaton if I knew that you were going to be putting that much power to the ground and what your actual use was. Sounds like a salesman with his proverbial head up his ***.

2001bluerata

iTrader: (2)

Looks like I got screwed on purchasing a HD eaton posi in my 12 bolt!

ataylors

iTrader: (2)

so it seems most of the breakage has come from "packaged" rear ends, the ones built by local shops seem to not have troubles. Except for the posi units, which I think the "HD" units which usually means it has stiffer preload springs in it, would be worse on a DD because the clutches have to slip when turning. That would lead to more wear. The true trac should really help and I think non production line assembly is the key.

ataylors

iTrader: (2)

what about gear noise? How many have it/dont have it?

SILVERZZ28

iTrader: (3)

can you shoot us the part # for the tru trak?

MeentSS02

iTrader: (11)

SSmokin...was the True Trac a straight drop-in? I was told that it might not be due to the Strange axles being a little different than the Moser axles that are usually used with these in their 12-bolts. I'll give the Eaton that came in my Strange a shot though...I don't do any heavy drag racing at all, so I'm sure it'll live...it's a matter of whether or not I like it for daily driving.

zlover129

iTrader: (10)

^^^you reqouted all those pics just to ask for a part number? Just delete the img tags man and save us all some screen space

SILVERZZ28

iTrader: (3)

fixed

Now shoot us the part #

SSmokin 01

iTrader: (14)

Model # from the box. It's also stamped on the diff in the pic.
914A576 TT GM 8 7/8 33T


It dropped right in for me. I put new carrier bearings on, swapped my 3.73 ring gear, and used the same shims. Backlash was within spec as well as wear pattern. I don't have any ABS now though. This is a 3 channel rear (No ASR).If you want that you'll need to have the case machined and have a reluctor ring welded on. You can see the ring on the broken diff in the pic.

4 channel with the rings on each axle may not have this issue.

I bought mine local. This is what comes up at Summit if you punch it in.

SILVERZZ28

iTrader: (3)

Thanks! I need a 4series though. I'm looking on summit but no luck
EDIT


found it

http://www.detroitlocker.com/images/LTPCAGweb91305.pdf


DTL-914A575 $419.95
Estimated Ship Date: Today




Brand: Detroit Locker
Product Line: Eaton Detroit Lockers
Aftermarket Carrier Style: Detroit locker
Cover Bolts: 12
Carrier Series: 4
Axle Shaft Spline Quantity: 33
Manufacturer of Axle: GM
Carrier Material: Steel
Quantity: Sold individually.
Notes: Fits 4.10 and numerically higher gear ratios only.

A little cheaper too

2 fast 2000

iTrader: (4)

I thrashed a Moser 12 bolt w h/cam & nitrous. Left at 4000 rpm on slicks , no bottle and broke the ring and pinion ( which was a richmond ). I think it broke due to Moser setting it up wrong or to lose, but whatever.