I have an 81 CJ-5 with a 258 and a t-176 4-speed / Dana 300 combo.

I have found a 78 CJ-5 with a V8 and a T-18 / Dana 20 combo. It is a factory V8 and I am sure the T-18 came factory.

What is involved in swapping the V8 t-18 behind my 258? I am mainly concerned about attaching the tranny to the engine. Not real worried about any of the other stuff like driveshafts and crossmembers etc. Just differences in BH and clutches etc.

If I can do a budget upgrade to a t-18, I would like to do so.

My guess is that it would be a pretty simple deal, but I want to make sure. I will need to part with some significant cash to buy the other Jeep so I don't want an expensive yard ornament.

Thank you for your time,

ROB

I have an 81 CJ-5 with a 258 and a t-176 4-speed / Dana 300 combo.

I have found a 78 CJ-5 with a V8 and a T-18 / Dana 20 combo. It is a factory V8 and I am sure the T-18 came factory.

What is involved in swapping the V8 t-18 behind my 258? I am mainly concerned about attaching the tranny to the engine. Not real worried about any of the other stuff like driveshafts and crossmembers etc. Just differences in BH and clutches etc.

If I can do a budget upgrade to a t-18, I would like to do so.

My guess is that it would be a pretty simple deal, but I want to make sure. I will need to part with some significant cash to buy the other Jeep so I don't want an expensive yard ornament.

Thank you for your time,

ROB

The stock bellhousing should work, don't be surprised if you need to drill and tap a new hole, the bosses should already be there however. The clutches are different if im not mistaken, as are the throwout bearings and maybe even the flywheel.

The T-18 has a deeper first gear and is inherently stronger, but if you are going to keep the Dana 20 on it and not adapt it to a Dana 300 it might be easier just keep what you have. The higher gearing in the Dana 20 kinda negates the lower gearing in the T-18 with respect to you current setup.

Good Luck

Give parts Mike a call at www.partsmike.com. he can answer all your questions and sell you the parts you need to make it work. I think I have all of 20 bucks into mine......

It'll bolt right up...just use the bell that is with the T18. the 304 (360/401) and 258 have the same bolt pattern and use the same clutch components.
the budget upgrade would be to use the T18/D20 combo....to keep the D300 requires an expensive adapter from Novak or AA.

And be prepared for a super short rear driveshaft.

I've done the swap to cj-5. The rear cv shaft is 12 inches long. I had to limit the center pretty short to avoid binding.

Here are a couple of other things that I have been thinking about.

I am planning on starting a SPOA on the 81 that I own. The rear axle is a reverse rotation so I get some help on driveshaft angle.

Plus the t-176 in my 81 has some issues with shifting. I think it is a loose fork in the tower, but it will only go into reverse everytime. The rest of time it goes into a forward gear only sporadically after "working" the shifter. I think the tranny is basically sound, and it has no bearing noise. Probably need to pull the tower to look inside and see. I've rebuilt a few so I think it would be an easy fix, but you never know.

I had a pretty good idea that most of the stuff was a direct interchange, but I wanted to make sure.

Basically the 78 that I am looking at has several things that I can use, and I am just making sure that it is cost effective to purchase vs. other plans.

That and I am just dying to get another non-running CJ. I'm now up to 4 CJ-5's........not sure why. Two run and drive, and two more are parts.

I guess it is better than other addictions....

I'm going to do some more thinking about the Jeep.

BTW- One last question.

In today's economy, what is a BH to transfercase T-18 /Dana 20 combo go for in running shape?

I know they used to bring a pretty good dollar, but that was years ago.

Thanks, ROB

And be prepared for a super short rear driveshaft.

I've done the swap to cj-5. The rear cv shaft is 12 inches long. I had to limit the center pretty short to avoid binding.
His driveline will be just as short as the '78 it's coming out of. That's a stock application in those CJ's (T18/D20) It should be about the same length as his current T176/d300 combo.
If your considering SOA, I would suggest moving the rear axle back a bit. There are guys who have SOA'd CJ5's and gotten away without having to, but the benefits outway the effort.