[BigEd36]

Originally Posted by Silver Surfer

The only time I have seen a welded differential is on low budget (can't afford a real locker, which is the right way to do it) 4x4 rock crawlers.

Thousands of oval track racers have used welded spider rear ends. The Camaro in my avatar had a welded diff.

[mafiacustomz]

ok your spec is 2.56 for the 91 caprice lo3 5.0 but the replacement ring and pinion gears from advance auto are 3.42 it was a mistake 3.72. I will check for the rpo code.

[fwinter01]

why not just up grade the clutch pack in the diff? Less money and no shimming

[mafiacustomz]

i dont know anything about rear gear if you can show me a link.

[cobalt327]

Originally Posted by mafiacustomz

ok your spec is 2.56 for the 91 caprice lo3 5.0 but the replacement ring and pinion gears from advance auto are 3.42 it was a mistake 3.72. I will check for the rpo code.

There are two different carrier series depending on the rear gear ratio:

• 2.56 and higher gears ("higher" gears have lower numbers, like 2.41, 2.29, etc.) go on the 2 series carrier
• 2.73 and lower ("lower" gears = higher numbers, like 3.08, 3.23, etc.) go on the 3 series carrier

You can install a 3-series gear on a 2-series carrier by using a ring gear spacer, but this is not advised for stick shift applications, or if there's a lot of traction, HP and/or weight involved.

[Jim Rockford]

[cobalt327]

Here ya' go:

[Mojo56]

Originally Posted by BigEd36

Thousands of oval track racers have used welded spider rear ends. The Camaro in my avatar had a welded diff.

That's right... and also thousands of drag cars had/now have welded spiders. No different than a spool or mini-spool. Common practice...

[rusthater89]

The limited slip allows the tires to slip. The outer tire in a turn needs make more turns than the inside tire.

When driving straight the differential will work as a single unit rotating both tires. When you make a turn the spider gears will walk allowing slippage so you don't get wheel hop and such. This is important and not a good idea for street driving to weld the spider gears up.

[jonahb]

Originally Posted by Jim Rockford

LOL, I cannot believe someone would do that.


Now back on topic, if memory serves me right, you have a 120 volt mig welder running self shielded flux core. IMHO If you are going to weld up the spiders, I would at least borrow/rent/whatever a machine that has more amperage like a 220 volt machine with 70s-6 mig wire or dual shield flux core (electrode/wire positive) because of the better penetration compared to the self shielded flux core (eletrode/wire negative). Just use your dryer plug in and make a extension cord if you do not have 220 volt outside.

I'm with colbalt327 and others about this being a bad idea, at least get someone who has done it before or a certified welder (with rigging would be nice ).

[1971BB427]

Originally Posted by AutoGear

EVEN dragracing its not a good idea. Think about driving through the pits and all the crud that can get on your tires; or turning at the end to go on the return road. One side has to slip somewhat somewhere or youre going to be unhappy. Best advice, get a posi axle and put under your car. Avoid Lockers and the horrible 'Gov-Lock' used under some GM cars

Excuse me for saying this, but HOGWASH!
Welding a rearend gear is a horrible idea for the street, but almost every true drag racing car is using a spooled rearend, and that works the same as a welded up rear, except much stronger.
They are not only a good idea for drag racing, but much better than a posi and stronger than a posi too. A spool or a welded rear is a bad idea on the street, but at the track a spool is great. That's where they were designed to be used.
And as for lockers; I've run a locker in my '71 Camaro on the street for over 30 years behind a 427, and it's not only worked perfectly, but it's been trouble free. The right locker is a very good option, and often a bit cheaper than some posi units.

[cobalt327]

I think we all pretty much agree a spooled or welded diff on the street is NOT a good plan. My take on the relative strength between them is this: Lincoln locker or spool really amounts to much the same thing strength-wise, because either one is still only as strong as the carrier and ring & pinion. But welded has the added chance of breaking due to the welds failing or because of the heat treatment being compromised by welding.

Either one can be too much for stock axles (especially considering the weight of an A-body like the OP's Caprice)- and w/C-clips, we all know what can happen when an axle lets go...

Going back to my first car, I used a welded diff in my '55 post w/a 301 and 3-speed manual. Was just dumb luck I didn't have a problem. Well, other than wearing rear tires out, squealing like a pig around every corner in town, and having to plan ahead if entering a parking lot or doing any lock-to-lock steering maneuvering.