derf

If you look back in AMC parts books you'll actually find the axle was the AMC 15 for a long time before it was called the 35. Turns out it dates back to 1962. It became the Dana 35 in 1985 when AMC sold the tooling. https://en.wikipedia.org/wiki/Dana_35#AMC_15

Depends on being able to find a donor axle with 3.73's. If you can, it's pretty easy. But if you get a non XJ donor, you're dealing with a low pinion. If you want to keep the strength of high pinion, you're going to have a hard time finding a factory equipped 3.73 axle. 4.10 would be easier to find since that was the ratio for 4cylinder XJs.

I went and did a little research and confirmed that the MJ axle is a good one. More like the FSJ and less like the CJ. The only reason I wouldn't use that axle would be parts availability on the brakes. It appears they were somewhat unique. If I swapped over to discs or managed to find a good source of parts, I would use it as well. I had one of those axles in my J10 and it was a great axle. The only reason I swapped it out was because I upgraded to a full float Dana 60 from a J20 (along with the front HD Dana 44).

Swapping to 3.73 in the front Dana 30 is probably the best option if going that route. Swapping out a whole axle is a pain. And any donor probably doesn't have the right gears in it so you'd have to regear there. The only reason I'd swap out a Dana 30 would be to get rid of any axle disconnect mechanism or go from low pinion to high pinion. My question is what exactly that rear AMC 20 is. There are two axles that use the AMC20 differential. The CJ style (AMC20) and the Grand Wagoneer style (AMC23). The CJ version has weaker axle tubes, two piece axle shafts, and is generally not much of an upgrade over the Dana 35. The 23 is a full half ton axle that is comparable to the Dana 44/Chrysler 8.25/Ford 8.8. Being new to the MJ, I'm not up on which version they actually used or whether this AMC20 was swapped in from something else. If it's up to the M23 level, I'd use it. Otherwise I'd skip it and go with something else.

Safety is a part of it. But the Wrangler is a body-on-frame vehicle. And those always weigh more than a similar size unibody vehicle. Beyond that, every generation of the Jeep keeps getting bigger. The CJ5 was bigger than the 3, the 7 was bigger than the 5. The YJ wasn't dramatically bigger but it wasn't any smaller. The TJ was a little bigger here and there. The JK was a bit bigger. The JL is bigger still. And bigger = more weight. The CJ2A was 2,120 pounds. The 2dr JK was at least 3,760. The 2dr JL tips the scales at 4,076. We're getting to the point where the base 2 door Jeep is double the weight of the original.

The Rubicon D44 in the TJ and JK were the "Dana 30 with a Dana 44 pumpkin" axles that need tons of reinforcement. The axle tubes, inner C's, knuckles, unit bearings, brakes, etc. are all D30 no matter which axle you get. The TJ is even a low pinion but they did switch to a high pinion for the JK. So that's been going on for a good long while. The JL axles have seen the return of the Center Axle Disconnect system and people are swapping them out left and right. I don't know if they are "true" 44's or just a continuation of the D30 with a D44 differential. But no one like the big gaping hole in the axle tube and none of the aftermarket companies are using JL based axles. They're using the JK version with different brackets. the JT Gladiator has a max tow package with heavy duty axles. I don't know if those are "true" 44's in the front or not.

It sounds like he's only doing the work on one head and leaving the other one alone.

Got any pictures? How much?

I know I'm looking for a rainbow colored unicorn and may not have much luck at all. But I'd like to put a factory roll bar in my MJ. I may just end up bending up some tube and making one. But if by some strange coincidence, you happen to have a factory unit laying around, I'd be interested in it. It's for a SWB, if it matters. I'm in Denver, which will probably impact shipping costs.

You'd be surprised at how fast scamming a bunch of people for just a couple hundred bucks can add up.

Stock JK rims come with something like 6.5" backspacing. Makes it easy to get a wheel adapter to go from 5 x 4.5 to 5 x 5 and not have it stick way out.

If you get an AX-15 from a newer 4.0 Cherokee or Comanche, it's pretty straightforward. The gearing will depend on exactly which transmission you get as well as the size of the tires you want to run. Bigger tires = higher number gears. If you go to http://www.grimmjeeper.com/gears.html you can just pick the transmission and transfer case (NP231) from the drop down menus and plug in tire size. Then play with gear ratios depending on what size tires you pick.

These days, it's a crap shoot. A NAPA starter has a better chance of being good than one from Autozone. Find a decent one and swap it. Chances are it will be good for a long time. If not, you just have to swap it out again.

Yep. That's a sure sign of a starter on it's last legs. Plan on a swap. Soon.

If that's the case, I should get mine done while I can. I have two cores myself. Would you want one or both of them in the deal?

1991 SWB 2WD Comanche 2.5 / AX5 / no t-case / 2wd front axle / Dana 35 / SWB Build date: Unknown (I didn't look yet) Current Location: Denver area Status: Non-running. It's been sitting for years. It's had at least one roll over accident in its life and it has a few other notable indications of damage (rear passenger side bed side, front driver's door, bumper and bed, etc.) Notes: Looks to still be pretty stock. Current owner: Me Plans: Going to get my other MJ trail worthy and then do something with this one. Or I might see if I can just get it running and sell it to someone who wants a project.

1987 Comanche SWB 2WD 4.0 / Peugeot BA10/5 / no t-case / 2wd front axle / D35 rear / Short Build date: Unknown. Sticker was removed or painted over Current Location: Denver area Status: Sitting for years, unknown running condition. Looks to be stock drivetrain. Notes: No notes yet really. The bed is pretty well beat up. Still straight-ish but it definitely took more than one hit and looks worse the closer you get. Collision damage reported in 2012, it's probably been sitting for that long. Current owner: Me. Plans: 4WD conversion. Switch over to AW4, Atlas transfer case, front Dana 44, rear Ford 9", front long arm kit, rear spring over, fenders cut and bump stops to fit 37's.

Looking good. I just helped a buddy do a water pump replacement (the arm up to the viscous heater broke off) and we did all of the rockers and a new timing belt since it was about that time anyway. That's an "interesting" motor to work on.

Yeah, I figure that bed is good for a trail rig. I'll pull the fender flares before I cut the openings for the tires. Someone will want them.

Why does there have to be a point to it?

I'm probably going to end up with a set of aftermarket wheels. Still probably 15" rims because big wheels on old trucks just look... weird. We'll see. I'll probably change my mind a dozen times before I get a chance to get started.

I was looking at 275s for the rear. That seems like a popular width. Thanks everyone for the info.

So I'm running some ideas through my head about building up my 2WD as a fun sporty truck to run around in. To support a V8 swap or other power increase option, I want to have some good size tires in the rear. But how wide can I go before I start sticking out of the wheel well? I know I can tub the rear and put in some pretty massive tires but I don't want to do that much work. And I don't care about actually going to a track and competing. But it would be nice to make some use of the power on the street. So if I pick the right wheel with the right offset to get the rear tire very close to the frame/spring on the inside, how wide can I go before I get out from under the fender flare? Assume for the sake of argument that the tire diameter will stay close to stock. The only change would be the width. Front tires will probably stay at or near stock size because they fit and work just fine. And I'm not trying to turn this into a race truck in any way.

Mountain Off Road makes conversion brackets. https://mountainoffroad.com/collections/wrangler-tj/products/4-0l-straight-6-motor-mounts-97-06-jeep-tj You do have to cut off the original frame horns and weld these new ones on. But it's not difficult work.

That may be true. But a bad steering stabilizer will not cause death wobble. A good one won't fix it. FCA issued a TSB that basically indicated the fix for complaints of death wobble was to replace the steering stabilizer. https://autorepairdenvercolorado.com/repsponse-to-chrysler-fiat-tech-bulletin-on-jeep-death-wobble/