500-comanche

Ok guys, I need a little help with my memory. It looks like I will be resurecting the MJ after all. It's an 89 that needs a new engine. It has an AX-15 and is 4x4. If I wanted to go to a HO 4.0L do I need to watch out for one that was matched up with a 5spd? What would need to change if it was an engine out of an xj with an AT? I used to be pretty well versed in this stuff, but I guess after 2 yrs and a new born baby my memory is shot. Thanks

I think ur doing the right thing. If ur not comfortable with it and don't have the facilties to do it, I wouldn't attempt it either. I am doing my first 4.0 swap, and I wouldn't say it was easy in the least bit, and I just got out of a year of votec auto tech! That year has about a mile of vaccum hoses to figure out. labeling helps, but overall, it is not an "easy" swap IMO.

I finally got the 4.0l out of my mj tonight. It took so long and I was so cold and tired, I didn't even get a chance to see what happened to it. Tomorrow it gets gutted and I can see which ring I lost. Those two star bolts at the top of the eng/tranny mounting hardware are a royal pain in the.... I think I will be taking the tranny out and then putting them back in together. Or is that a bigger pain than just doing it the old fashion way? I hope I can remember where each of the million and half vaccum hoses go! I am leaning towards a reman. engine. I have done some research and I think this will fit my needs the best as far as time/budget. It's still going to to be a few months anyway before I can afford to much of ANYTHING to it. But I can't wait.

Not sure if u have done this yet, but try just adjusting it first. There is a great article at jeepforums.com in the cherokee tech FAQ on how to do it. IT may be in this forum too, but I saw it over there for sure. It will go a lot faster/more accurate with a voltmeter.

OK, well I finally got this fixed. What I did was clean the the throttle body by removing it and taking both sensors off. I cleaned every hole and orifice ;) with carb cleaner and paper towels. I used almost a whole can and cleaned it up really good. When I took the TPS off, I didn't notice how it was set, and had to adjust by repeated trial and error. It took about 20 times of loosening and tightening the sensor and moving it a tiny bit until it would run well. I don't have a volt meter so I had to do it this way. I will have one to use tomorrow and will adjust it the right way. Regardless, the RPMs never drop below 1K now! W/ the meter, I can set the TPS so it idles a little slower and runs a little smoother. I don't know which one helped more, the TPS adjustment or cleaning the T body, but it works much better now. My guess is the TPS adjustment is what helped the most. Anyway, thought I would let everyone know the problem seems to be fixed! :D

Nothing mentioned so far would account for a 6+ mpg loss, except for the brakes. You mentioned that you replaced the 02 sensor. That would have been my 1st guess. Are u sure it wasn't cracked during installation? Possibly, you got the wrong 1? Are there any other factors? How does the engine run overall? Does it have normal power? Check ur O2 sensor again. I'm not sure if ur engine is L-EFI controlled or not (L-EFI is FI with airflow meter that checks the amount of air flowing through the intake manifold). The meter might need to be replaced.

extended brake lines. If ur only going 2" in the rear you probably don't need to change your pinion angle. I went 2 in the front and rear and haven't had any problems. If you go 3 in the rear, i have heard you need to change the pinion angle. Other than that, you should be OK as far as I can think. Ur control arms will be fine, u may need a track bar extention for the front, but I'm not sure.

Well, I will try to keep you all updated, but it will be a while. It happens a couple of times per trip so I will have to live with it. I am way too busy this week to take care of it due to a bunch of new issues this week. Thanks for all the input everyone, I'll let you know what's up ASAP.

Yes, it will recover if I give it a little gas (IF I CATCH IT IN TIME OF COURSE!). So you think it's the TPS? That would make sense. Any special tricks/warnings to replacing it? Thanks for you help!

It stalls when I have the clutch depressed. I am coming to a light and I push in the clutch to put it in N or down shift or just hold the clutch in to coast. The RPMs drop down all the way down till it stalls, or it recovers. It pretty much runs great other than that.

I have an 89 MJ w/ 4.0L and 5-spd AX-15. When I take it out of gear to neutral, then the rpms drop- sometimes to the point it stalls. I don't think that it is fuel related. I was thinking it might be a vacuum problem or maybe the EGR? Would appreciate any input you fellars might have. Thanks.

I have an 89 MJ with a 4.0. A few weeks ago I rearended someone and had to put a new rad in it. Everything went fine and seems to work fine. The engine temp seems to be cooling fine. It takes about the same time to warm up as it used to. However, since then, I get very little warm air out of the defroster, and no warm air blowing through the lower heat ducts. If I turn the selector to defrost, moderately warm air comes through the defrost vents at the correct level of flow from 1-4. When turned to heat, no air flows through at any of the levels, but the defrost still works (esentially no difference between defrost and heat settings). What would cause: 1) only moderately warm air to come out of the defroster on defrost 2) No air to be pushed out of the lower heat ducts on heat

:yes: :clapping: :yes: Good one!!!

I have had really great luck with the Dupli-color Truck bed coating in a rattle can. It costs about $8 a can. I bet about 1 or 2 cans would do the trick. I would give them a light sand with finer grade sandpaper and spray them with some POR. Then spray on the bed coating. It applies better this way than herculiner too. It really comes out well and looks good. It really doesn't run at all either! (within reason of course). I don't think I would actually ever use it for a bed liner, but I sprayed my grill, blinker brackets, etc. and they look great. I just sprayed my bed toolbox with it, and it looks really good too because it doesn't run. Test it first on some metal though. If u change your mind, it could be a real :mad: to get it off! Remember, it's not AS tough as Rhino or herculiner, but it IS pretty tough. :chillin:

Yikes! Well I understood a bit of what you all said. I now realize that this is 10X more complicated than I first thought. I would still like to attempt this someday. Fortunately, I know a retired mechanic who spent 30 years working for WA state as a master mechanic and has forgotten more than most mechanics will ever know. I am sure that he can answer this question, but I will ask you guys (again). Can I use the running gears out of a newer rig with a D44 and slightly used gears?

I am one of those fortunate SOBs that has a factory D44 in the rear of my mj. It has four leafs, so I know it is one of the heavy payload trucks. :brows: However, it has 3.07 gears, which makes no sense to me that it would be set up as a heavy hauler with such tall gears. :nuts: My ? is, can't I take the running gear out of almost any d44 from any other truck, be it Chevy, dodge, etc. and swap it in the MJ? I called the u-pick and they said they had 4.11s for a D35, but isn't the carrier different? Admittedly, I have VERY limitted knowledge of running gears, so any edumication you all have to share is much appreciated 8)

I got a cat back with 2.5 inch exhaust with a magnaflow for $170 installed. I don't really recomend the magnaflow though, I think there might be a little more bottom end power, but I actually think I lost a tiny bit in the mid-upper range. I was much more impressed when I went with a dynamax on my old yj (of course, it's totally different on that short of a rig). My muffler was $100, and I have to say I am a little dissapointed with it. It sounds good though. 8)

Anybody remember that guy/company that was selling a 4" lift in here a while back? He was basically advertising a lift he and his company were developing and I think it was about a 4" lift. I haven't really been in the forum for a while so for all I know it is one of you guys. I don't think it was the hell creek guy (Tom?). I wish I had more info, but I think it was aroung $400-$450. Maybe I am just remembering things that weren't really there. :nuts:

OK, I know, I know, the same old questions about the same old topics. I did a search, but had a difficult time narrowing down what I was trying to find out. So here is the question- Can anyone tell me the following: Will 31s fit under an MJ without rubbing with a 2" lift and no trimming? What length of bumpstops would I need? Please include current stock length to what I would need to keep from rubbing. (seems like if it's a 2" lift, 1" oughta do it?) What length of shocks would be best to provide a good ride while helping to reduce rubbing? (again, seems obvious that adding 2" longer shocks would take care of it) At what valving? If I am using stock 15X7 rims, will I need BS or spacers and if so, how much? Thanks, for the help. It's late and I am tired so I tried to be as specific as I can. I really want to get going on this ASAP and would love to stay with a 2" BB instead of jumping to the extra cost of a decent 3" (no AALs for me!) My beloved MJ is my DD and hunting, camping, light 4X4 truck, not a rock crawler, so a smaller lift is fine with me. :D

Please don't make drop brackets for the leaf springs. PLEASE don't! Call up Tom on the spring rate, he'll get you worked out. Why do you feel so strongly about the brackets? I could understand your position better if I knew why u say this. This guy is very talented. The drop brackets would be built over the existing ones with the new eye 3" lower and back about 11-12mm, with 1/4 inch steel and boxed on both sides. He has done a number of these for others for much bigger trucks with great results.

How many inches do you get from the chevy shackles? I want 3" of lift for the rear on mine.

Much of this thread applies to some of the questions I have about lifting my MJ. I have an 89 MJ LB with an 4.0L 5spd. It is the ax15 AND it has a D44 in the rear with 3.07 gears in the front and rear. I doubt it is the metric ton package because of the manual and high gears, but the 44 is built for the truck, it indicates the gearing on the diff housing, and YES IT IS A 44 AND I CAN TELL THE DIFFERENCE!. Anyway, I want to lift it 3" but maintain the best ride I can and the load capacity the truck has (I am ashamed to admit what I have asked this thing to haul) :oops: all while keeping it as cheap as possible of course. I work with an expert welder who offered to build some drop down brackets for the rear while I get coils for the front, but I need to get this thing set up asap and these springs could be just what I have been looking for, but I don't know what spring rate I have, or what I should get.

sweet thanks for the info!

I want 3-4" of lift on my MJ. I would like to find something from the junk yard or parts rig. I have heard that ford truck springs will work, but don't they give about 6" of lift? I only want 3-4". Is there a chevy, dodge, etc. that would work? I know an upcountry from a zj will work for 2" but they are hard to find. Just wondering if anyone knew of another spring set that would work on Mj/Xjs. Thanks! :cheers:

Anybody know which fuse goes to the cig lighter. I could look it up but... yawn... I was hoping I could cheat and ask u all.