I've been lurking for a while, but decided that this may be worth a post. I was unable to find any posts of anyone doing what I've done here so I would like to share. Bear with me, I'm trying to put as much as the information I've come across in one place as I can.


I've been dealing with the ambiguous transmission hunting gears (or torque converter locking and unlocking to be more specific) for a while now on my 98 24 valve 3500. The transmission started acting up quickly after a fresh hd rebuild.

Initially, the transmission shop told me it was a known ground issue with the trucks and to make sure all grounds were perfect, so I took a grinder to every ground point on the truck and made sure the grounds were perfect (I also treated them to prevent corrosion). At the same time. I cleaned all positive side connections as well. In what seems to be a normal pattern, it seemed to solve my problem for a short time. I suspect that part of this could be due to resetting the apps without really knowing about it.

(see https://www.dieselbombers.com/24-val...tml#post897661 )

While generally not doing the entire procedure as outlined above, the batteries are likely to be disconnected at some point while dealing with grounds. I suspect this is another reason it's so hard to tell if anything actually works as a fix when you make a change.

The problem went away for a while, but eventually, and slowly, came back and got progressively worse.


After the problem started to come back, I was changing the oil and managed to contact the alternator stud while changing the filter.



When I looked at the guard around the stud I decided it was protected and thus did not disconnect the battery. This blew the 140amp fusible link in the fuse box. No parts stores carry a fusible link at that high of a rating in that size (although they do carry them in that size and style... up to a whopping 70amps). The local dodge dealers in the Atlanta area where the truck is for now said it would take a week to get one. That type of delay was unacceptable because I needed to be able to drive the truck and having a working alternator is rather helpful to that end. With the apparent limited availability of that rather innocuous part I hope everyone carries a spare.

In my case a replacement was unavailable so I went with a different route. I picked up a 150amp DC circuit breaker. I kept the alternator wire going to the normal stud in the fuse box due to wire length issues and ran another wire from the same stud to my circuit breaker.



Instead of going directly from the breaker to the other terminal on the fuse block (this would be the one the wire from the battery goes to that the fusible link normally bridges across), I ran another wire to the battery. This also allows me to disconnect the alternator from my battery during oil changes without having to mess with the battery terminals.

I did eventually end up putting an identical breaker in line on the wire from the battery to the fuse block as well. It is very convenient to be able to disconnect the electrical system this way, it serves as a backup breaker for the alternator (I could swap the wire back to the fuse block and not use a breaker easily), and if something goes bad with the vehicle electrical system, I'd like to be able to disconnect power (or have the breaker trip) and possibly prevent a fire.


The problem seemed to disappear again for a little while, and once again came back.

I attempted the apps reset procedure as outlined above, and it went away for a short time and was back (although not as bad) the same day. Then I did the apps adjustment as outlined here:
https://www.dieselbombers.com/98-5-0....html#post9867
Pictures are here:
https://www.dieselbombers.com/24-val...tml#post441111

Mine was out of adjustment and I adjusted it. I did make a newbie mistake and fail to make sure my multimeter was reading correctly. During a later voltage check on battery voltage it wasn't reading correctly. I did check again with a calibrated meter and my actual is now at .549 vs .539 on the tag. This is much closer than it was originally and I elected to leave it as is.

I did read about wrapping aluminum foil over the alternator wire as well as segregating the apps wire from the harness with the alternator wire or purchasing a noise filter. It seems fairly difficult to fully isolate that wire from the harness. I assume that not all harnesses take the same routing as an early 24 valve such as mine.



I see there is some type of plastic block holding the various wires together at the alternator. The harness takes a rather inconvenient course around the front and side of the engine, picking up wires as it goes. At the point the apps wire goes into the harness it is is quite large and goes down by the motor mount before wires start separating out again. It is about as inaccessible as it can get and looked like it'd require removing some accessories to do that way.

I decided that I would come back to the alternator wire if I still had problems and ran a ground wire directly from the driver's side battery to the apps mounting block as well as another one to the PCM.

The problem came back so now I went back to the alternator wire. I decided I had been looking it all wrong. There is nothing inherently special about the factory alternator wire itself, other than that it causes interference and heartburn for those of us with automatic transmissions.

I was able to leave my batteries connected during this because my circuit breaker allowed me to isolate the alternator wire from the rest of the system. Normally you'd have to disconnect the batteries to do this.

After some measurements and considering on how I wanted to tackle this I went to my local NAPA and got 8 ft of 4 gauge battery cable as well as 2 of the smallest terminals they had for that cable (I should have gotten a part number, but it's 1/4" hole). I test fit one terminal on the alternator and found that the rather ineffective shield was effectively stopping me from using the terminal. However, a little clearancing with a grinder solved that conundrum.



I laid the cable out on the route I wanted to take and checked for potential problems, rubbing, or interference. I decided to route the cable from the alternator towards the battery where I joined the cross cable. In hindsight the cable could simply go to the passenger side battery if a new fusible link was installed (or if I had relocated the circuit breaker in my case).

I ended up cutting a short length off the cable. So it probably ended up being around 7'8" or so. 8' should be about perfect to go to the original alternator wire stud in the fuse block, which is where I would have sent this if I still had a fusible link.

NAPA only had black cable in stock uncut, so I painted the first and last few feet red. I then proceeded to be impatient and handle the cable to quickly and mess up my nice clean paint job while I put the ends on the cable.

The cable follows the cross battery cable on top of the radiator. The wire loom isn't quite big enough to put it inside, but I might get a larger loom at some point so they can be bundled together better.

 

I zip tied the cables together along the length, ensuring that there are no sharp points of contact where the cable could end up rubbing. I will also be checking on the cable periodically to make sure I did not miss anything. On the other end the cable follows the battery cable as it starts to go towards the battery and continues to the fuse block.

The entire install would look much cleaner except for the messy look from the current routing for my circuit breakers (and the messed up paint). I zip tied both ends of the original cable out of the way rather than cut them off in case I ever wanted to put it back to the original configuration.




I'm still working on how to clean up how my circuit breaker install looks. Because I mounted them on the top of the fuse block cover, I have to leave enough length to access the fuses. I made sure the screws were short enough to not compromise any fuses and then cut down the points after I installed my breakers. There is an extra wire going from the battery to the breaker that provides power to the fuse block. I noticed a little corrosion on the factory wire that now goes to the breaker when I installed it and even though I cleaned and treated it I wanted to make sure a voltage loss from corrosion was not contributing to my problem.






I've only driven 100 or so miles since I did this change, but the biggest thing to make me optimistic is that I did NOT have to disconnect battery power to the truck to do this (I just opened the breaker for the alternator) and I did not do an apps reset afterwards. By simply disconnecting the original alternator wire and installing this new one I went from a truck that was hardly drivable with the torque converter locking and unlocking to everything acting completely like it should.


I hope this puts an end to my headaches with this transmission. I originally planned on taking this truck up the alcan this year to get it home to alaska pulling a trailer, but between this and now the Alaska highway being washed out it might wait until next year. I don't want to be dealing with transmission issues on a 5000 mile drive while pulling more than 10,000 lbs.

 

Did you happen to have the alternator tested? I had trouble with mine doing all that business and was able to stop it by zip tying the wires running by the alternator up and away from it. Has been nearly a year now and no more trouble. I had the alternator off recently and tested and while it still charges it failed one of the tests for a good one. So in my case a bad alternator is causing my shifting issues.

 

I have not had the alternator tested. Do you remember which test it failed? I will keep it in mind to get it checked at some point.


The wires seem to mostly be bolted to the alternator, so did you pull them away right as they came off of it?

 

I don't know which test it failed. I did speak with a cuz who works around this type of stuff every day and said this was not uncommon. Seems like he mentioned diode leakage.

There are a couple wires in a split loom that run by behind the alternator and not attached to it. I zip tied those to the upper alternator bracket nice and snug.