Thoughts on Jeep Comanche?

Asking on behalf of my buddy Chris. I know he has been casually searching for one of these for quite a while now and yesterday I received an email asking for my thoughts on this one:

https://albany.craigslist.org/cto/5327917512.html

I gave him as much info as I could remember regarding the early XJ/MJs from my own Cherokee search and get down in an email during my lunch break (which is the best help I'm able to offer being 300+ miles away). Chris went to look at the truck last night and is now on the fence about making an offer.

Here's what I know about it:

-Its an '86 with a carbed 2.8

-3 speed auto (Chrysler Torqueflight I think??)

-Appears to have a bit of lift (3-4" maybe??), new coil springs in the front unsure how the rear was lifted (just remembered, MJs were spring under right? So maybe spring over swap??)

-"...runs a little rough, don't know if it needs a tune up or if it's driveline vibes..."

-"...interior is in great shape minus the floor pans, new floor pans are included"

-Exterior seems ok and pretty rust free from what he said, although I think it was dark by the time he was checking it out

-"Guy has a bunch of other Jeep/Dodge parts and vehicles, including a 4.0 he may try to throw in to sweeten the deal"

Chris is thinking about going back tomorrow for a second look and offering $2500 if all seems well. My thoughts are that's about the right ballpark considering it's fairly rust free for upstate NY. Seem fair? What would you pay?

I'm also wondering about this 4.0 the guy supposedly might be throwing in - how easy of a swap is that in place of the carbed 2.8? Thinking more in terms of the wiring than anything, because these years could have either a carb, Renix, or TBI right? Is the chassis harness common amongst all the FI/carb setups? What about swapping to the later Chrysler FI? Probably would make sense to swap to an AW4 at that time too, yes?

That 2.8l V6 is the same GM 2.8l V6 that was in S10s and Camaros of similar vintage. It's got the GM metric 60° bell housing bolt pattern. So throwing a 4.0l in to sweeten the deal, will still require a different transmission to swap in too.

A lot of folks used to swap the 3.4l V6 in place of the 2.8l, GM sold it as a direct replacement for a while, might still.

The 2.8l got a bad wrap, it's no power house, but by it's last year in the Jeep, which was '86 (I think) most of it's reliability issues were worked out.

That transmission should be a TF 904, which has been used behind every 60° GM engine swap you can imagine.

I'd be looking for a '90s early '00s FWD GM car with a supercharged series II 3800 to swap in place of the 2.8l before I went to the trouble of swapping a 4.0l into it.

bigdaddylee82 wrote: I'd be looking for a '90s early '00s FWD GM car with a supercharged series II 3800 to swap in place of the 2.8l before I went to the trouble of swapping a 4.0l into it.

Wouldn't you still need a trans since the 3800 is 90°?

How about a fly and drive for this?

https://grassrootsmotorsports.com/forum/open-classifieds/1986-jeep-comanche/107285/page1/

More fun than welding in floor pans.

In reply to EvanB:

No, the L67 uses the same 60° bell housing bolt pattern, so does the LS4 if you need a V8. The Jeep/AMC 2.5l would be a direct swap too, but why bother?

Thats the same 2.8 thats in my blazer. Its anemic so i would look to swap something in as soon as possible if hes keeping it long term. Mine ran rough until a good carb cleaning and fresh air filter.

I'd get one that already has a 4.0L in it. I think there's something with the firewall on the early Comanches that makes fitting the 4.0L in there difficult. Plus, 4.0L I6 >>>>>>>>>>>>>>> wheezy 2.8 GM V6.

So I think I'm going to steer him away from this particular truck. Sounds like a swap isn't necessarily very straight forward and based on some of his comments I'm not sure he would be happy living with the 2.8 long term.

I'm now hearing he's going to look at another one on Friday, a 4.0 5 speed '88. It's definitely got the choice powertrain combo, but seems to have been used as a plow truck so rust may be a concern. Guess he'll have to see.

What's the scoop on Renix?

I would make an offer as if I was buying a rolling chassis because as mentioned the 2.8L is something he will probably not be content with. Being it is a carbed 2.8 a oM617 or other non- copmuterized desiel would be good swap option IMO. The rusty floors is not uncommon and he should factor in new door and window seals to prevent that from happening again. He should crawl under and check spring hangers shock mounts and see how the spring over in the rear looks. Does it have the D35 or does it have the AMC20? Being it is a 86 it is possible it has the single piece axle AMC which is a big plus IMO. What year is the 4.0L, if it's pre 91' it is the Renix and Its not as desirable, and it's really only worth parts price because it will be more trouble than it's worth to swap in. All this being said if he is not interested in a motor swap I would pass on it.

^ He's the "Renix Whisperer," I'd listen to what he says.

Ok I was about 3 mins to late on my last reposnse. Lol I just brought my wife's 89' Comanche back to life and it is a Renix truck. All trucks are renix up until 91'. I would pickup a 91' and up if possible but the Renix is not all bad but they require alittle special attention. I replaced every electronic component on the truck including the ECU. The grounding system is weak and requires beefing up and that will help solve a lot of problems. To save some headache I would factor in replacing these parts/sensors on the truck if they have not been done recently: TPS, Knock, Map,CPS, Injectors (use the 4 nozzle Volvo injectors), ECT, o2, fuel pressure regulator, fuel line quick connect orings. Comancheclub.com has a ton of great info and I would look in the DIY section at crusier54's Renix tips. I could write a book but this is what I can think of off the top of my head.

Mmmmmm...carbed 2.8 GM V6. Never could figure out why they put overdrive transmissions behind those, since the only place you could use it was downhill.

In reply to ridinwitcj73:

Jesus! With all that possibility, a GM V6 swap doesn't sound that bad.

Appleseed wrote: In reply to ridinwitcj73: Jesus! With all that possibility, a GM V6 swap doesn't sound that bad.

any vehicle with 20+ year old electronics would need the same.

fyi tail lights are NLA and go for $200-400 per light on ebay.

In reply to ridinwitcj73:

Lots of good info there, thanks for that!

So here's the other truck he's going to see:

https://longisland.craigslist.org/cto/5293814133.html

The low mileage and "shop truck" designation doesn't exactly give me the warm and fuzzy feeling when it comes to things like sensors and o rings having been previously replaced. Hopefully any issues are obvious enough to present themselves on a test drive, although I think he's a competent enough mechanic to know whether or not he has a turd on his hands.

MrChaos wrote: fyi tail lights are NLA and go for $200-400 per light on ebay.

Good to know. Thanks!

3K is a lot for a 2.8L Comanche even if its clean. If you friend was closer to MA I might be tempted to sell mine.

So, is my understanding that 4.0 powered Comanches are not all that common correct?

I don't think you could consider a Commanche to be common at all. There's 3 or 4 years with the 4.0, but at least around here, they were not a very hot seller.

I had an 86 with the 2.5 AMC motor. It was dead slow, but not as slow as the 2.8.

I live in Arkansas so we do not have to deal with the salt like you do up north but the snow plow attachment scares me alittle, but I am sure he knows what to look for when it comes to rust. If the bed is rusted much those are getting harder to find. My wife's truck set for 4 years before I took the project of making it road worthy on. if the truck is driven ever so often it's likely the components under the hood are in better shape then what I had to start with. There are ALOT of plastic vacuum lines under the hood that are probably brittle and ready to snap in two if you look at them wrong. You can buy replacement vacuum harnesses, there is a front and rear, but if you delete the egr valve you can get rid of a lot of those lines. Another important plastic line is the map sensor line. I have not been able to fine a stock replacement but some guys use steel brake line. I just used a rubber vac line. A lot of the parts stores do not stock parts for these trucks so plan on waiting a day or two if he needs parts. The 91'+ parts are easier to come buy. All this said I love our little Comanche. They are fun to drive and they turn heads. It was worth the trouble and money. After working on our VW Passat it was a joy to work on the Comanche. Lol

the drivers and passenger floor pan will need to be replaced even if it came from the south, they all rust there.

Tried sending you a message but it failed. If your friend is interested I have a 1988 Eliminator 4.0L manual thats been swapped to 4wd with about 5" lift.

ridinwitcj73 wrote: Being it is a carbed 2.8 a oM617 or other non- copmuterized desiel would be good swap option IMO.

Is it wrong that this idea is strangely very appealing to me? Small diesel 5spd 4x4 truck (or SUV - I assume this would work well for the Cherokee as well?)

What's the scoop on Renix?

Compared to the later chrysler EFI system, the wiring insulation and connectors seem to be made of crappier stuff so it's way more common for them to have wiring problems and crumbling connectors. It also requires a different and much less common scanner connector if you want to hook a scanner to it. When it's working right it's fine. The power difference between that and the later HO motors is only apparent at higher rpm (and the newer ones still dont feel 'good' at higher rpm anyway). If not for the maintenance/repair issues i really wouldn't have any preference either way.