Starting on MJ restoration, and find some dents in the floor. Subframe okay?

[jkchr1s]

Hey guys,

 

I just picked up a 87 4.0 4x4 shortbed MJ and was tearing out the carpet (it was stinky and disgusting) and to check the floor pans for rust. I saw some concerning dents around where the bellhousing/trans that are dented downwards facing the ground. I initially thought the previous owner had the front driveshaft break loose and dent up from the bottom, but the dents are bulging the wrong way for that to have happened.

 

Are these stress marks from a collision? Does this mean the subframe is twisted? I don't know how you'd dent from the inside of the cab downwards...

 

The rest of the body is in pretty good shape, I bought it because it only has some surface rust. There are 2 small dents (one on the driver's side front quarter panel, another behind the passenger door towards the bed. At first glance, I thought they were just dents that I could easily fix. But now I'm wondering if it's because maybe the whole thing is twisted.

 

Are these dents cause for concern as far as the subframe goes? I intended to do a full restoration on this truck, but now I'm starting to worry that the subframe may be bad.

 

Thanks!

Chris

[Pete M]

weird!  got pics of the front frame area?  do the doors close fine?

[jkchr1s]

The doors don't close very well, but I assumed it was because the bushings were worn out... you have to kind of pick up on the door to get it to fully close. Where the pin goes on the side of the cab for the door latch, each side has a crack towards the inside of the cab that flexes if you move the pin around. The driver's side front bumper is pushed

 

Where in the front frame area do you want to see?

[Pete M]

all of it ideally.  I've got no idea what might be going on. 

[jkchr1s]

Ok, I'll take some more pics tomorrow when it's daylight. Thanks!

[jkchr1s]

@Pete M Here's some more pics... as far as I can tell the frame itself is okay. What do you think? Put some new carpet down after fixing the rust and forget about those dents?

 

It's still bugging the crap out of me... how in the world do you dent it from the inside around the bellhousing area?

[Strokermjcomanche]

That damage likely came from a higher front end impact . I would check the firewall /apron areas . Any of the panels in the front look like they've been changed ? 

[Dzimm]

Yeah that truck was wrecked in the front end.  Get some pictures of the inner fenders under the hood and search the frame rails and fenders from under the front of the Jeep.  Stand back a few feet and look straight on at the panel gaps for your fenders and doors as well as the gaps around the hood.  Also measure the cab to bed gap on both sides.

 

As long as you don't find anything crumpled or cracked on the frame or close to it, and it drives straight down the road I wouldn't be too concerned.  There isn't much you could do about the crumpled sheet metal without putting it on a stretcher.

[jkchr1s]

Yeah the guy I bought it from said it was in a minor accident in the front, but it wasn't a bad wreck. The front bumper is pushed in on the driver's side and the driver's side panel has a crumple right at where it meets the door. I crawled up under it before I bought it and looked at the frame as best I could and it seemed to look good to me, but I'll take a second look at it before I put too much more money in it. I'm starting to think it wasn't so minor to see those crumples now that I'm seeing the floor and adding that together with the drivers quarter panel and behind passenger door.

 

The doors absolutely do not shut correctly, but the body has 277k so I figured it was just worn our bushings. You have to lift up on the driver's door and hold it just in the right spot to get it to latch properly. The pins on both side of the cab for the door latch have cracks around them from the doors improperly closing. Is that signs of rust on the back side of cab?

 

It's hard to know if it drives straight at this point because the front passenger universal joint on the axle was absolutely shot. I pulled the intermediate shaft, replaced the ujoint, and put it back in, and now it's leaking gear oil. Don't want to drive it much like that, and from what I've seen, I need to disassemble the front diff and replace some seals in there. Which brings me to...

 

Seeing how it has 277k on the body, my plan was to buy a wrecked ODB-2 XJ and swap the engine, trans, axles, and interior... but now I'm kinda scratching my head wondering if it's worth the trouble with this body. I bought it thinking it just needed some body panels and an engine rebuild. I've already done new brakes all around, WJ master cylinder/booster, new brake distribution block, power steering pump, cap, rotor, wires, plugs... and after changing the oil and running it bit here and there it quit smoking but developed a nice low end knock.

 

With 277k on the clock, once I did an engine rebuild I'm willing to bet the AW-4 will let loose and I'll need to rebuild the trans. I should have known better, but the body itself just has some surface rust, and it's what I thought was in pretty decent shape for a 33 year old truck. Certainly looked the best out of others I'd looked at in the area for the price.

 

I've been shopping for donor XJs, but I'm starting to wonder if I shouldn't be shopping for a better MJ chassis to start with.

 

Thanks everyone for the input, now I need to get her back up on jack stands and really look over the frame, firewall, and make sure this is the chassis I want to pour my time and money in to.

 

[Dzimm]

Don't start hanging your head on it, just want to dig into it deep to make sure there aren't supprises later.  My 97+ truck was wrecked as well, the driver's side wheel came through the floor pan from what I can tell.  Still drives and does everything just fine.  These trucks are unibody so even a minor accident can cause all kinds of wrinkles and tweak stuff all over the place, doesn't mean they are junk, just means you need to know what all is damaged and fix stuff that doesn't work such as your doors.  Just don't expect to make a show quality truck out of it but will be a great daily driver or offroader.   

 

As far as mileage goes, I wouldn't be too concerned.  The 4.0 is a bullet proof motor and the AW4 is a similarity reliable trans.  I've never heard of an AW4 go bad.  Worst thing I've seen go wrong is the solenoids but that's an easy fix.  I also wouldn't worry about the motor unless it's knocking or making noises.  As long as it's not overheated and the oil is changed you won't have issues for a long time to come.

[Eagle]

One simple (partial) check is to park it on a flat, level surface (in a garage would be ideal, if you have one) with the wheels pointing straight ahead, and use a tape measure or even a length of wire to measure the distance between the front and rear hubs on both sides. IIRC, you can find the correct dimensions in the FSM. See if both sides are the same, and if they match the specifications.