O.T. trans interchange?

If I could jump in here.

That's one thing that GM did right. From about 1955 on, they will all interchange as far as bolt pattern goes--(almost) any Chevy tranny will bolt to any engine & visa versa.

You don't mention what year you are working on, but consider this:

Yes, you can bolt it up, but the trouble lies in the shift points: That diesel tranny is a shifting, jerking nightmare and it is compounded when it is tied to a gas engine. I just don't think you are going to like the way it feels.

The 700 grew out of the old 350 transmission (it is nothing more than an overdriven 350, and to this day is still the same design from the center back), which made its debut in 1982. It took GM until 1991 to get the thing straightened out and make it somewhat bulletproof.

Then, in 1993 they went electric, which in my opinion, is the best thing they ever could have done.

It is my favorite tranny, but I suspect this is because I have had to work on so many of 'em. :>)

Like RJ hints at, any of 'em prior to the '91 model year belong in the scrap yard.

Hope this helps,

Allan

Hope I have this straight.

You are going INTO a '85 sub with a 350 gas engine. Right?

That '91 or '92 tranny should drop right in there as the only electric part of it is the electrical torque converter lockup. The electrical plug should be the same on both.

Just make sure that the speed-o-meter output is the same on both. I.E. Both gear driven or both ESS. (Should be gear driven on that gal, I would think.)

Good luck,

Allan

One more thing before you run off....

If you are planning on towing, the main thing is the tranny cooler out front....Be absolutely certain that it has an external cooler.

Heat is the only enemy an automatic has and towing causes heat.

Tryin' to help,

Allan