86 MJ complete 4.3 swap

Hi guys, I just picked up a clean 86 mj with 116,000 original miles. The 2.8 has picked up a knock on cylinder 6 so time for a swap. I have built an awesome 96 XJ but this one is new to me. I would like to swap the full drive train 4.3 vortec and trans and tcase. I would like to stay kind of pure in the fact this one had a chevy v6 from the factory so that is what I think would be an awesome setup. I have been searching for days with little success on any write ups on this. I know I could do a 3.1 or 3.4 but would like to get a package that had four wheel drive in the first place. Now I am not saying this is set in stone just trying to do on a budget. Any info would be awesome. I know a 4.0 would be cool but not to pumped on a 4.0 as not a ton of power and man am I tired of the damn header cracking, yes I have brown dog motor mounts and trans mount so no movement and also have a flex pipe installed in the down pipe right before it hits the cat to eliminate the torque effect from body flex. So hope I dont upset anyone and just need some guidance.

5.3 why waste time with a 4.3

So the 5.3 all the guys I hang out with over here say the 5.3 is a pain to get in and then have cooling issues since not much room. I have no idea as I don't drive one.

I am in need of some guidance from any one that has taken on a project like this for some help. I would love the 5.3 but same thing as the 4.3 don't know anyone with a complete setup. Anybody out there put a 5.3 in an 86 comanche????? Or even a 4.3 in a Comanche??? Help would be awesome.

I know a handful of people have done 4.3's AND 5.3/6.0's into XJ's would basically be the same. Novak adapters makes anything and everything you need to swap in. At the very least, I would go with their engine mounts, exhaust manifolds and radiator. That is what I am going to start with anyways.

Yeah that is cool i am hoping for no adapters. I don't want to connect to a ax-15 with a v8 or even the 4.3. I would rather do a full drive train. That is my dream a Street sleeper Comanche.
I am not knocking your view just a different out come.

rockchucker said:

Yeah that is cool i am hoping for no adapters. I don't want to connect to a ax-15 with a v8 or even the 4.3. I would rather do a full drive train. That is my dream a Street sleeper Comanche.
I am not knocking your view just a different out come.

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Never said you have to have adapters for trans, other than maybe crossmember and trans mount. But, Novak makes engine adapter mounts to bolt-in to XJ/MJ.

FrankZ, JohnD, xj+rcks, and a few others have done 5.3/6.0 swaps with trans. I suggest reading their threads.

A 4.3 + T5 swap, drivetrain from an S10, would work really nicely.
The trouble is that the 4.3 isn't *that* much better than the Jeep 4.0.
So you are going to the trouble of a drivetrain swap in order to get something marginally better than what was factory available on different years of the same vehicle.
Unless you have a butt-ton of work into the suspension / body / interior, I wouldn't bother.
~10 HP & 30 ft-lbs gain over finding a Commanche with the 4.0 doesn't justify the swap...

On the other hand, a 4.8 / 5.3 / 6.0 - or even a fuel injected Small Block Chevy - would be worth the effort.