Comanche from donor Cherokee

[Tomahawked]

Picked up a perfecly straight bodied 2wd 89 Comanche. Interior is clean and unmolested. It also came with a wrecked 91 4wd Cherokee. Both are/were 4.0 powered. Comanchee was a 5 speed but minus motor & tranny. My intention is to swap everything over to have a 4wd Comanchee. I want to go back with an AX-15 if I can locate one for cheap enough. Otherwise I will use the auto tranny from donor. Should I expect any problems with electricals between the years? It came with a couple of extra ECM's, and not sure for application yet. Also have a complete later model dash assembly that I need to find out what years its from. I am expecting everything to be a near bolt up without complications since I will have both side by side. I figured the axle from manual tranny is a different ratio from the auto, so will probably use both axles from donor too. Any suggestions and helpful hints would be greatly appreciated.

 

I am a loyal Ford guy thats heavily into early Broncos with 5.0 efi conversions. But its hard not to like these little pickups. I also have an old CJ-5 thats very close to being completely restored to looking new again. I have noticed how similar a lot of components are between Ford and Jeep, so hopefully won't have too much trouble figuring a lot of this stuff out.

[Pete M]

Should I expect any problems with electricals between the years?

 

The 2 have completely different systems so as long as you stick with one or the other, the issues will likely be minimal (and I'm talking about swapping over everything from the 91 if you go that way, including the stuff under the dash). But keep in mind that the automatic trans is computer controlled. So if you stick with the 89's electronics and swap in the auto, you'll have to integrate the trans computer into the system (and I'm not entirely certain if the 91 trans comp will communicate with the 89 engine computer so you might have to get some junkyard parts to make that happen). Likewise, you'll need to remove the trans computer and related stuff from the 91's harness if you go with a stick.

I think the simplest way (and it's been done before) is to swap over everything from the 91. And yes, the axle ratios are different between sticks and autos.

[Geonovast]

I figured the axle from manual tranny is a different ratio from the auto, so will probably use both axles from donor too. Any suggestions and helpful hints would be greatly appreciated.

 

Remember that the Cherokee is an Spring over axle for the rear and your Comanche is spring under. New perches will need to be welded to the cherokee axle.

 

Front is literally a bolt on. Worst part about it is you'll need to use the 4wd calipers, so therefore a bleeding is in order.

[Eagle]

As Pete said, they are totally different. The 89 has a Renix ignition/injection, the '91 is a Mopar. The 89 has a mechanical speedo, the 91 has an electronic speedo.

 

The good news is that I believe the engine controls from the 91 can be used stand-alone. Jeep used to sell (and maybe still does) a MPFI conversion kit for the older 4.2L Wranglers that originally had a carburetor. The conversion is basically the entire MPFI setup for a '94 Wranger 4.0L. If it can be retrofitted to an older, carburetted vehicle, I can't see any reason why you can't drop in the motor and assciated controls without rewiring the dashboard and chassis.

[Tomahawked]

I still need to drag the Cherokee over so I can start tearing everything apart. It also has the extra dash and other surplus parts in back. It isnt a problem swapping out the entire Cherokee wire loom and newer dash components to get the Comanche completed. I would much favor this over buying a retro kit to wire in. I have gotten used to plumbing in efi wiring into early Broncos without buying kits available. This looks a little less complicated, as most should be plug and play. In the process of acquiring these, I ended with an `82 Grand Wagoneer. Its only use to me is the axles for other interests. I hope to piece it out, but not too optomisitc about getting very much sold.

[Eagle]

It isnt a problem swapping out the entire Cherokee wire loom and newer dash components to get the Comanche completed. I would much favor this over buying a retro kit to wire in.

I wasn't suggesting that you buy a kit. I was suggesting that by buying the '91 Cherokee you are getting the kit, "on the hoof." You should not need to swap in the interior harness unless you really have your heart set on tearing out the dashboard and then reinstalling it.

 

My whole point in mentioning the Mopar kit was to show that the engine controls can used used stand-alone.

[pingpong]

I am stripping my 91xj at the moment. If you are careful and you split the tape that holds the wiring loom in place you will see that you can totallty seperate the Mopar FI set up from the wiring harness. it is a PITA, but it can be done. WHen I truggy'd Pong.. I remember ther being a difference in fuel pump pressure and 2 pumnps being available... not sure if that is a change from the early 4.0... or when they changed again later in the late 90's(just something to think about).

[Tomahawked]

Definately sounds like a good option. I will have the donor Cherokee here in a few days. There is an extra complete dash assembly laying in the back of that Cherokee. It is supposed to be a newer model than in Comanche. PO may have already figured on swapping out everything. With the electric speedo and fuel injection differences, I will most likely swap everything from one to the other. That way I can make sure nothing is crossed or missing. It takes all the guess work out. Chasing down electrical gremlins in electronically controlled systems is a total pita. And I don't want to find myself stranded out in the middle of nowhere if it happened.