Hi!

As I’m not getting 9” rear end anytime soon , I’ve decided that in the mean time I will try to strengthen the current rear end that’s already installed, that is GM 10 bolt 7.625 inch with 3.23 gears.
I’ve heard that with a few simple procedures you can contribute a great deal to its durability and strength, so I’m asking you for any advice on what can be done, like for instance welding of tubes, additional strengthening of casing, so it can’t deform etc etc...
At the moment I’ve got stock casing and Auburn Gear Pro series LSD in the center and 26 spline stock axles I think.

1. Is it wise to invest money in some aftermarket (Moser, Strange,...) axles, because the next year I’ll probably install 9 inch rear?

2. What must I be careful about when welding tubes? Is it possible that the casing deforms due to welding?

3. Is it necessary to extract the axles, before the welding?

4. Is it possible to weld something on the casing to enforce it, so it wont deform?

5. I’ve also heard that instead of stock bearing cap bolts, you can use ARP bolts. As I come from EU, its kinda difficult to acquire these bolts. I’ve been searching through many catalogs but I can’t find them. Do you have any idea where to get them? What is their part number?

When I bought LSD differential I also received some sort of additive for differential oil (friction additive). Do I have to add it every time I change oil or just the first time. Where can I get this additive? Why is this additive important?

Thanks!

 

May be some ideas in the following link:

http://www.ws6transam.org/10bolt.html

http://www.spohn.net/product.cfm?productid=1416

JamesC

 

1: Aftermarket axles are around $125. You'll need 26 spline axles unless you change the carrier to accept 28 spline axles. More cost. You decide.

2: Excess heat causes warpage. If the axle tubes distort, the axles won't be true and could break easier. You weld small sections at a time alternating around the tube.

3: No unless you're using an alignment jig.

4: Yes and no. The strength needed is across the back. It's better to install a solid cover with bearing cap supports like a LPW cover. It's difficult to get a proper weld onto a cast housing.

5: Factory bearing cap bolts are fine. I wouldn't even bother to upgrade the ring gear bolts in the tiny diff.

The additive is required for a LSD. You need to put it in the oil every time it's replaced. Your local parts store should carry it. Your local GM dealer should have some also.

You're planning on upgrading. Run what you have until it breaks. A stock diff has been broken by a V6 and a stock diff has survived behind a big block. No matter what you do to try and beef up the diff, the weak link is still the tiny ring and pinion which will probably be the first thing to break.

 

What is the difference between solid bearing spacer and crush sleeve? Why is solid bearing spacer better?

How can I convert 26 spline to 28? Is it possible?
What modifications does the carrier need? How can I do that?


I have an option to manufacture very strong axles, but I would like to keep it simple and stay with the 26s.
Why are the 28s stronger than 26s? Are there any other differences other than the number of splines? Are they thicker?
The way I understand it is that 28 have 2 more teeth (same size as 26) and are thus thicker a bit.

 

the spacer is a solid chunk of metal. once you torque it down right, it stays there. even when you beat on it, or retorque it.
the crush sleeve is like a piece of pipe with a budge in it. its tightened until you start to crush it. if you crush it just right, its like a "spring" that holds the preload on everything. if you overcrush it, or its beat on the wrong way, it gets slack.


to convert from 26 to 28 you need 28 spline axles and a new 28 spline diff.

28s are stronger just because theres more surface overall for everything to transfer thru.



in anycase, i think this is all a horrible idea.
because you can spend over 75% of the cost of a 9" trying to beef up your 10bolt... and it can still break the next time you drop the clutch.
its like beating on a drinking glass with a hammer.
it breaks easy..... so you can go out and get a thicker drinking glass.... but you'll still break that with a hammer..
or you can take it easy with the first glass, until you get your iron kettle.... then you can slam it with the hammer all you want.
(yay, kitchen references on a car forum. lol.)

if saving up for a 9" is hard on you.... then dont throw your money away investing on the 10bolt stuff.

 

^^^^^^^^
I've got a severly beefed 10-bolt, but only because I got it for basically nothing, as-is. If I was gonna spend any money, it would be dropped into a piggy bank until I could afford a 12-bolt. The small gear is more liable to break.

- My suggestion would be to put a aluminum girdle cover on, run it till you break it/buy the 9", and hope the pieces don't go through the cover so you can sell it later. It doesn't take long before you have in the 10-bolt what the 9" costs, and you still only have a 7.5/7.625 10-bolt.