Will it Fit? CJ5 w/GM 4.3 Auto Trans

Hello everybody,
This is my first post on this forum. I apreciate your help.

I Have access to a good running 1989 S10 4x4 with a 4.3 V-6 and overdrive trans.
My question...Can this Package... Complete with the 700r4 trans and Transfercase be adapted into a 78 CJ5? I am concerned about over all length and drive line angles.
I would apreciate your input. Feel free to E mail me at Reaney_in_nh@yahoo.com if you would prefer.
Thank you
Reaney in NH

 

First of all welcome to the board. Not really sure about the fit. Might be a good idea to take measurements of the overall drivetrain length, and compare to whats in a CJ5 now. Of course if you were doing a CJ6, then I would say yes it will likely fit. Good luck.

 

First, Welcome from Portland, OR!


The 700r4 is really too long to fit in a CJ-5 especially after adding in the length of adapters, etc. Another problem is you will probably run into issues with the front drive shaft clearing the trans pan rail as there is a bulge that sticks out in just the wrong spot on the 700r4. It's do able if you want to push the engine as far forward as possible and move the rear axle back. Depending on how much lift you have, you may end up having to go to a high pinion rear axle to alleviate rear drive shaft angles, read custom axle= expensive. If you are dead set on an auto trans, then the TH-350 is about your best bet as they are significantly shorter than the 700. Get out the tape measure as previously mentioned and you'll see what I mean. The 4.3 is a great motor and with throttle body injection is the easiest of the FI engines to retrofit. Several here have done this in early CJ's and I'm getting ready to do the same only with a manual trans. You might look in the knowledge base as there is an article about just that with some great insight. Nickmil.

 

Yeah I would think the TH350 with the D18 tcase, abd the warn overdrive would be ideal if you wanted the auto trans.
Of course you could always try to adapt the jeep tub to the S10 frame R)R)

 

I just re-read your post and realized you have a '78 CJ which means you "should" have a model 20 transfer case. That will make things even worse as the rear output shaft is high up on a model 20 making for even worse driveline angles. Nickmill

 

Thanks for the tips... Just to Clarify.

First of all.. My CJ 5 has no engine, no trans, and no Transfercase... I plan to use about 4in of lift. I will have Dana 44 front and rear.
I happen to own the 89 S10 and know it to be an excelent Engine trans combo. I had hoped to use the Engine with Fuel Injection, and the 700r4 and transfer case fropm the S10... I was afarid it mite be to long and was hoping someone had tried this combo.
I do have another option with a Granny low 4spd and transfer case from a 1980 Chev 1/2t P.U. I'm fairly sure thatr is a sharter pkg than the Auto trans.
I am still in the Planning stages.... unfortunatly all of these parts in still in MN and I am in NH. LOL My plan is to haul it all home early this spring and start on the project.
Thanks for the Tips.
Reaney in NH

 

I was thinking about putting my 89 gmc s15 v6 into a cj5 jeep glad some people are doing it so when Im ready I wont have `any surprises.

 

The 4.3 is one of the most popular CJ swaps. Auto transmissions can be a challenge even in the longer 1978 CJ5's. First thing I was thinking was mating an Jeep NP231 or GM 241 with a passenger side drop. (GM NP241 input shaft supposedly swaps to the Jeep NP231 to spline up to the 700R4) That still makes a huge overall length of 23.375" for the 700R4 and 20"+ on a NP231/241. I measured my T90 + D18 + adapter + bell sitting on my garage floor. It is approximately 27" total (16" shorter ).

 

I'd say go with the granny tranny. It should be an SM465 if it was original to the 1980 truck. It's a good transmission. With the 4.3, it would be a really cool combination. Of course, I'm partial cause I'm doing something similar to mine. You'll have to find a 1986-up 168 tooth flywheel because the one out of the 1980 truck will not work with your 4.3L. Good luck with your project.

mruta

 

Just a suggestion - I think the cheapest route would be to find a complete AMC Jeep and transfer the engine, trans and TC. If you don't care about the condition of the body or frame, such Jeeps are cheap in the NE (plow Jeeps - rust, rust and more rust!)

 

Hmmm.... Cheaper??? I already own the 4.3 eng, The Granny low 4spd and transfer case. How could I get it cheaper than already owning most of what I need? Plus get Fuel Injection?
Drive shaft Mods and Engine mounts.... Alot of which I can do myself.

Besides.... Then it would just be another Jeep.... LMAO.
Thank you for all your help everybody. I will keep you posted as this comes together this summer.
Reaney in NH

 

Yeah, installation of stock drivetrain has to be cheaper than any swap. You may be able to piece it together without buying anything more, but I doubt it. Which transfer case is behind the SM465? Does it drop on the passenger side? Will it need to be clocked?

Just trying to be realistic - you should be able to pick up a rusty CJ for a couple hundred, or less. Plus your Jeep will be worth more with the stock drivetrain than not. Add up the total cost: cheaper, definitely.

 

I agree that stock is cheaper. But an SM465 behind a TBI 4.3 is coooool! 8)

 

You'll need to get out the tape measure and take very close measurements of your drive train, not just length but width as well. Some of the transfer cases from full size vehicles are just too wide to fit between the frame rails of CJ's. Depending on which transfer case you have on that SM-465, it could possibly be as long as the automatic combo you have. The adapter frequently is 4-5" long alone, then add the length of the rear output if it uses a slip yoke.........
There's an old saying in swapping circles that says "Just because you have it laying around doesn't make it a cheap or good swap". You'll find this statement in either Novak's or Advance Adapters catalog also, and I've found it to be very true over the years. Nickmil.

 

Hey Reaney- I was looking at Novak's website earlier this morning. If you haven't seen it, you should check it out (www.novak-adapt.com). While I consider it to be a good source of information, I noticed some incorrect information regarding the Chevy 90 degree V6. I only know because it took a lot of reading to figure out what I needed to put a flywheel and hydraulic clutch on what used to be an engine bolted to an automatic. If you do decide to install your 4.3, feel free to email or PM me anytime.

By the way, got pics?

mruta

 

I just looked and noticed the statement about the Flywheel not interchanging with the V-8's. That's true about the 200 and 229 because of their semi-odd fire design, but not about the 4.3. The '85 4.3 shares the same flywheel balance and bolt pattern as '85 and earlier two piece rear main seal 350's. In '86 they changed the crank flange and balance of the 4.3. It does share the same pattern and balance of the '86 and newer 305-350. The part #'s are even the same! You just have to make sure the bellhousing you are using will accept the right diameter flywheel you intend to use as many of the bellhousings that came with the 153 tooth flywheel were smaller and the 168 tooth flywheel would not fit inside. This is true of all small block Chev V-8's also. Nickmil.

 

Just reviving an old thread, it comes so close to answering my question but not quite. I've got a 1991 GM 4.3 TBI, and looking at a pre 1980 SM465 that's currently behind a GM 350. Will the flywheel from the older 350 work, or do I need a 1986 or newer flywheel from a 4.3 or a 5.7 ? I was thinking 700r4 but now I've found an sm465.

Paul

 

Yes you need a 4.3 flywheel since the motors are externally ballanced.

 

You gotta love Tim always touting the AMC parts! I like the way you think Tim!