so pretty much here's the scenario. Front differential exploded as seen in the picture, pinion gear no longer exists, yolk was melted and seperated from drive shaft, transfer case sounds like a machine gun. still drives after just removing front drive shaft, however no 4x4, so I'm going to pick up a whole new front clip from a junk yard. any suggestions on anything else I should take a look at or consider replacing since I'll have the front end off anyways? its got 142k miles so I'm sure there's got to be a few things, any advice would be much appreciated.

 

that looks very much like a lack of maintance issue there, the previous owner must have been lazy on the diff fluid changes, from the sounds of whatyou have described you will also need a new t-case bc it sounds like the chain snapped(the machine gun sound)

 

Is that ths skid plate the gears are laying on? If so, that's an indicator that the previous owner NEVER took the time to change out any fluids. I'd do a complete fluid changeout i.e motor oil(mobil 1 synth), tranny fluid plus filter(s)( mopar atf+4 ONLY!), transfer case, and both diffs. JMHO.

 

It helps if you tell us what you are working on as I found it in one of your posts:

Quote:

got a 99 5.9 4x4

If it just broke the chain in the transfer case you might be able to save the transfer case if you remove it from the truck, break open the top and replace the chain and check it out good.

You stated that you had to "get a new front clip", this means the front grill area of the truck with head lights as well. You mean you need to get a new front differential. You are going to have to find one from a donor truct that is a 1998-1999 and that's it. The others should be different as yours should be the 194 FIA front differential. Also remember you must find one with the same gearing as the rear in your truck wether it is a 3.55 or a 3.92 gearing ratio.

That is the skid plate that the gears are on guys. That plate doesn't look like it has ever been dropped "OR" has never been cleaned. When ever I dropped mine I always cleaned it out just in case I dropped something in there you can find it.....LOL..... Anyway, it looks like a fun project but in reality, it really shouldn't be that hard once you find a new one.

 

yeup thats the skid plate that the gears, bearing, and the fragments of the front diff. are laying on. Now I forgot to mention that just before this "explosion" of events I had the truck in 4 wheel drive but had put it 2 wheel drive before I got on the highway. Which kind of makes me wonder if in addition to the lack of previous maintenance if it hadn't fully dis-engaged form the 4 wheel drive and that's part of the problem. If you take a look at the other picture I attached you can see that the yolk going from the drive shaft to the front diff. was completely seared off which I'm guessing caused the fire (oh yeah btw when it happened and I looked under the truck the front diff. was on fire). Also just one more thing I thought of that I'd throw out there while I'm at it, when I shift the truck into reverse it "clunks" into gear I guess you could say, doesn't do it with any of the other gears just reverse, something to worry about?

 

I would assume that you were not fully out of 4X4 and what you experienced was axle bind. This would explain the front diff, the T-case, and the rear diff "clunk".


If you weren't fully out of 4X4 and axle bind was the issue then you are going to have issues with all 3. Most likely the "Clunk" is the rear differential backlash because with the axle bind it wore your gears so badly it is out of specifications for backlash and as the gears engage with the torque the gears move TOO much causing the "clunk". Get someone back there and see if the clunk comes from the rear differential. Also you will need to open the inspection cover, drain and inspect.

Most likely the T-case chain is broken or stretched causing the "machine gun" sound. If stretched it will roll over the gears teeth without turning them. If you continue you will shear the teeth off and you will have to replace the gears and teeth, however if the gears are worn because of the bind then you will have to replace them anyway. Remove the T-case and open the top lid and inspect.


Please take pictures and host them to www.photobucket.com then after it is fully uploaded go to the picture and copy the entire link under or on the left side that says [IMG] at front and back, (Copy the whole thing) and paste here. This will insert the full sized picture here. Do not move the picture in your account after as then the link will be broken.

 

alrighty can do, I'll get the pics up as soon as I can get around to doin all of it. Just out of curiosity is there something I should be checkin out that may have caused it to not fully disengage from the 4 wheel drive in the first place? or should that be taken care of since I have this tingling feeling that I'm going to be replacing pretty much my whole drive line anyways? Would it be worth rebuilding the internals on my existing transfer case or should I just look to pick up a complete one from a junk yard or someone who's parting their rango out? aaaaand while I got all this tore apart would there be anything you could recommend I do as a HP or torque gain?

 

No on the hp gains.


First thing first, open the rear diff and open the transfer case take pic's (and measurements) and then talk.