Eagle

I believe Jeep started using Chrysler paint codes in model year 1988.

I was going to say that the 232 (3.8L) doesn't have a long enough stroke to help a 4.0L, but I think I could be mistaken. The 4.0 has a stroke of 3.41 inches. The stroke for the 3.8L engine is 3.5 inches, and the stroke for the 4.2L is 3.895 inches. When you do the math, the 3.8L crank does increase the displacement a tiny bit -- but not enough to matter. Mathematically, the 4.0L is 3.96 liters. With a 3.8L crank that increases to 4.07L. Not much of an increase, but the increased stroke would possibly help increase the torque by a little bit. Since you're in Mexico, how about a crank from one of the big VAM engines?

232 crank? The AMC 232 is a 3.8L engine. Did you mean 258 (4.2L)?

There are ways it could be done -- but very labor-intensive. Several years ago, a friend needed a driver's floor pan for his Comanche. I had an '89 XJ junker. He bought a body shop tool for drilling out spot rivets and went along the entire length of both sides of the frame rail, drilling out the spot welds that attach the floor to the "frame." Then he cut out the section he needed and welded it back into his MJ. The same thing could be done sort of in reverse -- drill out all the spot welds, remove the floor pans, and then cut out the XJ "frame" rails and weld them back in under the MJ floor.

I wouldn't drive that at all, anywhere. With a unibody, the "frame" rails and the floor pan combine to make the structure. Each "frame" rail acts like a beam. The thing with beams is that it's the top and bottom that do the work -- the vertical parts are only there to keep the top and bottom flanges separated. The top flange (the floor pan, in a unibody) sees compression forces, the bottom flange sees tension forces, and the middle of the verticals is what the engineers call the "neutral axis" -- no force at all. Once any portion of the bottom surface gets weakened or broken, there's no continuous path for the tensile forces. Those photos are so bad that there's no question of "if" your truck is going to break -- the only question is when. One half-decent pothole with a 5-pound bag of groceries on the passenger seat could be all it takes.

No, those are the towing mirrors. The "flag" mirrors are the ones like in the link I posted above.

The Eliminator didn't have "flag" mirrors. Your mirrors should look like the one in Jtrux's photos (above). The "flag" mirror refers to the el cheapo mirror that screws to the outside of the driver's door, through the door skin. Like this one: https://images.duckduckgo.com/iu/?u=http%3A%2F%2Fhellcreeksuspensions.com%2Fimages%2FRides%2FJeep%2F3in%2520Comanche%2520(10).jpg&f=1

These might work, with some alterations: http://www.ruffstuffspecialties.com/catalog/XJRAIL.htmlhttp://www.ruffstuffspecialties.com/catalog/XJRAIL.html Found this on the Jeepin.com forum: I'm interested in that tube ==> channel idea, because that's exactly what I was thinking of but I didn't know that any standard steel shape would fit.

Better would be if you could find a U-shaped member that would replace the bottom and both sides of the frame rail in one piece, but I don't know of any source for such for the Comanche or Cherokee, So steel angle might be the only option. But ... 3/16"? I think 3/32" would be plenty, and 1/8" would be overkill.

RV cams aren't "custom" -- there are several companies who offer them off-the-shelf. Swapping a camshaft should be a lot less work and a lot less expense than doing things like decking the head. http://www.cranecams.com/product/cart.php?m=product_detail&p=23907

Then how about just an RV cam? Similar lift to stock (maybe even a bit more), but shorter duration and less overlap will generate more dynamic compression.

The 231 (Command-Trac) transfer case locks the front and rear driveshafts. That's why it's not supposed to be driven on pavement in 4WD. The fact that the two driveshafts turn together is NOT a sign of a problem, it's a sign that the transfer case is in 4WD. If you can scare up an assistant, jack up both rear wheels again. Have your assistant rotate a rear wheel back and forth, as far as it will go in each direction, while you try to shift into 2WD. This may relieve some internal stress and allow it to shift.

Now that you've mentioned "stroker," the big hurdle when trying to do a budget stroker is that minor differences between the 4.0L and 4.2L engines add up, and you get an engine with too high compression for street gasoline -- unless you're VERY careful about things like quench height, timing, and probably enlarging the combustion chambers a bit. So a budget stroker might be a natural for LPG. But I don't think that qualifies as either fast or easy.

I suppose it depends on your definitions for "fast" and "easy." The two ways I can think of are either installing new pistons, or decking the head.

Not right. See if one of your doors has been replaced. There should be a tag on the drivers door -- the VIN and paint codes should match your vehicle.

The Base models (or SporTruck, in some years) did not include a passenger side mirror, and the driver's side was the silly "flag" style mirror mounted on the door rather than the typical XJ style mirror that mounts to the front corner of the vent window frame.

Put a jack under the rear axle and lift both rear wheels off the ground to relax any stress on the drive line, then try shifting.

"If it ain't broke, don't fix it." My '88 XJ 4.0L is at 287,000 miles on the original lifters, rockers, and pivot balls. You have less than half that. If you're rich and enjoy wasting money, go ahead and replace everything, but the notion of doing unnecessary work to something you don't need to touch "just because I'm working nearby" doesn't make any sense at all to me. Just replace the guide seals and do the head gasket.

I found where he's talking about it. Does he do a write up on it? Sent from my HTC One M9 using Tapatalk Not that I can recall, but I think he's still alive and out there on the Internet with a blog. You might be able to contact him. If not, it should be easy enough to dope out the switch sequence. My guess would be that the last position is 4th with torque converter lockup. I imagine you would still need a shifter handle of some sort to go from park to reverse to neutral to drive, and the rotary switch just handles the transitions in drive.

The Mopar shades were made by Vent-Shade. They were the same exact product.

My first thought was a loose exhaust manifold bolt.

Then I would either rebuild the original engine to stock specs, or take the XJ engine, replace the main and rod bearings, and drop that in. The idea of a stroker engine is attractive, but it can't be done on the cheap. There are subtle differences between the 4.0L and 4.2L engines. You obviously can't use stock 4.0L pistons with a 4.2L crank, so you have to decide if you want to use the skinnier 4.2L connecting rods or the stronger 4.0L connecting rods, then you have to source pistons that will work with whatever rods you choose to get the right deck height. There may be aftermarket pistons available today that will work, but when I looked into it a number of years ago the available combinations resulted in overly high compression ratio, which meant running premium-grade gas AND having to be very careful about "quench." For me it wasn't worth it.

The 4.0 The 4.0L engine isn't overhead cam, so the front cover doesn't come off to change the head gasket. There is absolutely no need or reason to mess with the timing chain, water pump, or harmonic balancer just to do a head gasket. Valve lifters and cam lobes become work hardened from use. Replacing lifters without replacing the cam at the same time is very risky, and probably means the new lifters won't last very long. 138,000 miles is nothing to a 4.0L Jeep engine. I would just pull the head, maybe clean out any carbon on the combustion chambers, and reassemble. To do it right, you should have the head checked for flatness by a machine shop, and resurfaced if it's not flat. To do that, you'll need to remove the valves and valve train. Be sure to keep the valves, lifters, rockers, and pushrods organized so that everything goes back exactly where it came from. On my '88 XJ, I decided the replace the timing chain at 200,000 miles as a preventive measure, because I remembered that older AMC engines used timing chains with nylon sprockets. Got it open to find that everything was all steel, and there was no evidence of wear, slack, or slop in the chain. I put the new timing set in because I had already bought it, but I saved the old parts and I wouldn't hesitate to put them in a used engine that needed a timing set. Remember: If it ain't broke, don't fix it.

Everything you have mentioned is an option -- the question is, what are your priorities? Do you need to a fast & cheap swap to get it running, or do you want to put more time/effort/money into it to have an engine that will start out like new (the rebuild route)? Are you satisfied with the performance a stock 4.0L gives you, or do you want to boost the power as long as you're doing something?

Apples and oranges. He's talking spring rating, you're talking bed carrying load. The metric ton was rated for 2200 pounds -- which is what a metric ton is, hence the name.