sloboatnova

Hi, I'm Brent.

I've searched the forum, but didnt find answers to my questions.

I'm looking to buy a complete C4 IRS to put under a F-body camaro. I looked at one last night from an 84, but found stress cracks in the diff housing. I believe it to be a D36.

Which years have a diff housing that will swap over? I don't want to buy the wrong one if I go this route.

Also, being as the cracks werent really bad, should I consider trying to weld them up? My buddy is a profesional welder with access to good equipment. The cracks were towards the top on the driver side where the webbing ends. Is this a common problem.

sloboatnova

Moderator, I accidentally posted this in the C5 section. Please move it to the C4 technical. Sorry for the trouble.

WVZR-1

You could use any year but if you're looking to buy everything from one car I believe I might be shopping for newer '89+ parts. Anything '87 or earlier will have shoe in rotor e-brake and if you stuck with '89+ they have an actuator in the rear caliper for the e-brake.

If you've a high horsepower/torque engine you may want to make sure you're shopping for a D44 that's more substantial. An 8 1/2" ring gear vs 7 1/2" stuff. You can mount your IRS anyway you like and hang the knuckle/spindles where appropriate for what ever wheel/tire combination you wish and adjust the width with the half-shafts.

Do you have a car that you're using for a "mule" or are you just doing a from scratch build?

I would think you would want to avoid an '84 - the exception being if you stumbled upon an '84 with a 3.31 axle ratio and it would be quite valuable. There's not many out there so I wouldn't get excited. Do you know if it was out of an auto or a manual trans car?

COPO

I'm going to have one for sale in a couple months. It's a one off rear I built. Has Dana 44 that's rebuilt. I can supply brackets to weld in your car.

sloboatnova

Ok. When the time comes shoot me a price and hopefully it will be within my budget.

sloboatnova

Not sure what you mean by mule, but we are putting it in a 75 camaro.

What is the advantage of the caliper with the e-brake verses the shoe in rotor e-brake? Will these have different track widths?

rklessdriver

All 84's have the D36 rear diff. A d36 is IMO not worth the time, effort or $$$ to weld up if cracked. It is not common for them to crack unless they have been hit hard in a wreck... side impack collision on the wheel usually pushed the wheel/hub/halfshaft into the side of the housing and can crack them in that area or break the C-Beam mounting pad.

All the diff housings from all years are pretty much identical and interchange 100%.

Like WVZR1 said the later model stuff has a much better parking brake system.

The early model cars 84-88 also have a narrower track width which could be a good or bad thing depending on what wheel offset you want to use.
Will

WVZR-1

Mule would be a car of the same type that the same or similar has been attempted on and your effort is to improve on it!

I don't believe you need to be concerned with the track width. I believe you'll hang three components, the differential, the right/left knuckle/spindle combinations where your wheel/tire combination fits into the body and THEN you will have half-shafts built/shortened to connect the three components. I would think in the long run the later caliper/e-brake combination would be to your benefit. Many more sources for replacement parts.

sloboatnova

I'm also thinking the caliper e-brake will be better for playing. You know. To spin the rear end around and drift.

We don't have wheels yet so I could buy them at what ever offset needed.

Guess I need to keep looking for an 89 or newer d44. I'm in no big hurry.

thanks for the advice yall.

WVZR-1

Where are you located? I have enough NOS and new parts to put together a D44 with either a 3.54, 3.73 or a 4.10 ratio. All new either GM or Dana/Spicer. I also have the left and right knuckle packages.

sloboatnova

NOS is probably way more expensive than finding a used rear end, but feel free to put some prices together. I haven't gotten as far as deciding what gears to run. We are going to build a de-stroked hi rev engine.

I'm in Tulsa, ok 74115.