With HeyYou's help, I'm closing out the last of my critical electrical issues on the farm truck this week and moving on to more fun things. Next in line are problems behind the transmission.

1. Transfer case troubles

Tonight, for the first time, I got my shifter free by wailing on the linkage with a hammer and prybar. I also removed some stubborn transmission mount bolts while I had a good angle for future ease-of-access. The good news is it works great, no problems with the CAD vacuum or anything, all wheels spin and it shifts without fighting too much. The bad news is that there's a persistent noise coming from the case.

At any speed, the transfer case makes a rattle, almost a stuttering hiss that sounds like metal-on-metal. Kind of like making a slightly-too-fast cut on a mill. It gets louder with speed, but the pitch doesn't change, so I don't think it's the gears, chain, or synchros. It could definitely be a bearing or some kind of ring hanging on the shaft. Operation is smooth with very little lash. Any guesses?

2. Thrust Angle and Dangle

I've mentioned it before, but this truck is exceptionally dog-legged. It seems to me there's a hundred places the rear alignment can go wrong, but no adjustment points whatsoever. The rear axle is twisted 2 or 3 degrees right and have to steer noticeably off-center to go straight.

With the help of a lift, I got to see the whole thing hang free today and there's definitely something off. The right side hangs much lower and moves more freely than the left. I can't tell if it's worn springs, worn bushings, bad aligning pins or different limits on the shocks, but something's clearly uneven in the suspension. I definitely need new shocks and bushings, but those are bad all around. Is there anything I can do to trace the problem without just replacing things?

 

1. Lock the t-case in 4 high, then see how much you can turn the front driveshaft, before the chain tightens up. (have the cad unlocked will make this easier.....)

2. Dodge trucks are sorta famous for the 'dodge lean'. The drivers side spring settles..... and the truck sits crooked. Usually you have to replace the springs to solve it. Think I would have a look at all the bushings and such, see what they look like.

 

For the Tcase, that seems like a good course of action. I'll tell you how it goes next time I can elevate the front end.

As for the lean, I can understand that from a spring sag perspective, but I'm not sure it explains dog-tracking. I might get new springs anyway, the truck has earned them at 210k.

 

Long overdue update:

I've been avoiding the truck the last two weeks as I work on hunkering everything else down for winter in the new house. The garage is just a pile of boxes, wood, and tools that I can't use because there's no 220v power and no counter space.

I went to a junkyard to grab an extra tcase. You might say I wanted it... just in case! But seriously, that did not go well. The donor truck had a kinked driveshaft and smashed transmission support, and the front driveshaft was so seized to the flange that I couldn't get it off with a mini sledgehammer. Is there some secret to removing it? I didn't think there was a spline or anything on that shaft. It's still sitting in the yard with most of the bolts out, so I have a chance to go back and grab it.

I still haven't checked play in 4hi, and I have no excuse. I'll finally get a chance tonight, I think. The underside of the case is very damp, but I think it's mostly from when I opened the fill plug to check the level (and spilled), not from a bad seal. I also discovered that the noise changes quality depending on if I'm accelerating, coasting, or engine braking. Also, it does have a harmonic component that changes in unison with tire noise, so I was wrong about that. That doesn't sound like a roller bearing to me (since roller/ball bearings aren't torque sensitive), and since the gears are straight cut, there are no thrust bearings, so now I'm pretty convinced that it's a u-joint or chain.

I'm making a lot of guesses based on my book knowledge of mechanical systems, with absolutely no mechanic wisdom.

If it is a chain lash issue, what's my next course of action?

 

Just replace the chain. They do stretch over time. I know the one in my 96 (with 200K miles) is REALLY sloppy.....

On the t-case you are trying to get at the yard, is the case just shoved forward against the driveshaft? So it WON'T come out? Might try dropping the front of the shaft, and see if you can lever it loose. It's only held on by four bolts. (on both ends.)

 

The junkyard truck's front DS is dangling from the tcase. I already undid the connection at the axle and used the shaft as a giant cheater bar to break the flange bolts.

 

Wow. Hangin' on pretty tight eh?

hammer and chisel.......

 

Yeah, I think I need to get a punch in to one of the half-exposed holes and pry it out by that.

But I was just reading about the generations of the NP 241, and it reminded me that the donor truck has a different shifter.

Will a 98 case even work in my 96?

 

Not really. The newer case has a different shift pattern, the shifter mounts differently, and it doesn't have a provision of the VSS on the rear tailshaft.

The shifter, and pattern, aren't really too much of an issue, as the older shifter will work.... just have the wrong pattern on the ****, but, the lack of VSS is definitely problematic.