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Discussion Starter · #1 ·
Looks like I have blown out both limited slips in two of my cars. One has a factory unit which I believe is made by Eaton but, my GN has an Auburn which has lasted for a number of years. I believe the Auburns are not readily rebuildable and I need something that will withstand a hard launch.

I have heard mention of Eaton 800's and 400's but find no mention of such on their website. Pyle Brothers over in Baytown are a dealer for Eaton. Does anyone here have current knowledge or suggestions pertinent to the subject?
 

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Hey Steve, If you do a search on the Gnttype.org site there was a big decision about the different posi units at one time.

The I believe the Eaton was agreed upon
as the better replacement unit, I don't remember the model number.

I always used the stock posi unit and just
had it rebuilt (the kit is like $40) and they put in an extra spacer in the clutch pak to hold it tighter. Over the years I only had the posi unit rebuilt 3 times and it held up to a number of 1.46 60' times and
worked very well with no problems.

Take Care

Neal
 

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I would think that just a new set of cluches in the unit would make it almost as good as new. I over paid for cluches from the dealer but when I put my GM unit in my car I was happy with the way it operated.
Go with the eaton if you want the extra durability becuase looking at GNTtype, it looks like a much beefier unit than the stocker.

Joe

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1986 Grand National
TA-49, 009's, Hooker cat back, 3' BGC Downpipe with ported elbow and all the other usual stuff

 

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Steve,

I went through this a while back. I had an Auburn Pro Series that was opening up on me. The Auburns aren't rebuildable but I have heard of people taking the cone out, sanding it and them work again. I didn't go this route! I bought a new 30 spline Eaton like the one in the picture and so far it is pretty mean. The 400 and 800 are lb. ratings for the preload springs. FWIW the stock "S" shaped spring is rated at 200 lbs. When I ordered mine I was going to get the 800 lb. spring setup but was advised not too! Someone on E-Bay was selling a set of the 800 lb. springs so I asked why? His answer was the car acted like a spool setup and wasn't real nice on the street so he changed back to 400 lb. You are double with the 400 lb. over factory as it is. My car chirps a little around turns now so I made the right choice! If all you need is clutches then just do that but if you need a new posi get the Eaton with 400 lb. preload springs. Here is the link: http://www.gnttype.org/techarea/pictureguides/rear/eaton.html

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87 White T-Type [email protected]
 

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The first GN I owned came without a posi from the factory and I eventually ordered and installed the 800lb. Eaton diff. Other than the occasional chirp on sharp turns, it had excellent street manners IMO. I wouldn't hesitate to buy another one if the need arose!
 

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Steve,

I installed an Eaton in my GN a couple years ago because I wanted to upgrade the axles to 31 spline. I don't know which one it is though and will check to see if the info is on the box. It works fine.

Just a side note though, if I had not gone with the larger axles, my good old stocker would still be in there which was rebuilt.

Hank



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Hank Terry
87 GN, 10.95 @ 125
87 Ltd, 11.57 @ 117
http://turbocars.tripod.com (PowerMaster sales info & etc.)
 

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Discussion Starter · #7 ·
My GN was a pegleg and I had an aftermarket Auburn installed. Altho some seem to be able to revive them, they are a cone unit rather than a clutch style and are not readily repairable.

Hence the interest in the Eaton. Sounds like an Eaton with 400# springs should work fine. As I don't bother with slicks, it does not sound as if more pressure would really be advantageous.

My son's car has a factory unit and I will just rebuild it as they actually work quite well.
 

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I'm looking to replace my peg-leg with the Eaton unit. Gears-are-us is the best price that I've found on them...$339 + s&h.

How difficult is one of these to install? Special tools, shims, etc. I'll probably replace all the berings too.
Thanks, Rob
 

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I doubt this will help much, but I figure it's good info to spread. So for anyone who might give a darn:

I know a guy that has a Street Stock oval track car, which has to look all stock drivetrain wise and mostly suspension wise. He uses a Diamond-Trac locker in a 8.5 with C-Clip eliminators. The diamond trac isn't really a posi or a spool, in that it doesn't have a "constant pressure" type clutch. It has a ratcheting clutch so that the diff is full open until load is put on it. They work very well in road and oval track racecars. I've always wondered what it would be like in a street car, if you rolled around turns it'd probably act fine. I use one of these in my oval track car as well, which is a Ford 9" and it works great, takes a little getting used to entering turns, but it's the best thing I can recommend for a track that has two different shaped turns. The downfall is that (at least in a roundy-round car) they need rebuilding about every 30 nights, which is only about 1200 miles, but that's a far stretch from street driving.

Just $.02 for anyone who want's to reach down and pick it up.
 
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