electromanj

Hello all. I am having trouble with my 99 2500 diesel automatic trans. The scenario goes like this.
Starts off in first. Have to goose the throttle to get second. Stop. Put in park. Switch to 4 high. Then able to get clear to overdrive. Once I come to a complete stop and the tranny shifts to 1st, I have trouble to get it into second and can not get 3rd or OD. If I stop and put it park then switch to 2 high, no problems. This cycle continues. Once I am in first gear I have to switch from 4 to 2 or vis versa. I tried putting it into park and starting out again without switching the transfer case but it will not get past second and has a hard time to get 2nd.

My question is what would switching from 2 to 4wd have to do with the transmission not shifting up? I crawled under and found a red tube and a black tube that look like they come from the 4wd shift lever and end up at the vacuum shift motor. These connections were very loose. (Soft rubber). I put some hose clamps on them thinking I was a genious. I am not a genious. That did not help change a thing...

Thanks for any help!

Travis.

Lary Ellis (Top)

Have you tried resetting your APPS? (applied pedal pressure sensor)

APPS issues are VERY common on your truck.

Remove both negative battery cables and turn on a light so it drains any voltage.....leave them off for 30 minutes, then do the following.

Reconnect both batteries, put the key in the ignition and turn it to the on position (do not crank starter) turn it off, then back to on, off again and then back to on (3rd time) leaving it in the on position. Then depress the throttle slowly all the way to the floor and then back up. Turn off the key and then try the truck.

This is the reset procedure and sometimes it will help for awhile, most likely you need a new APPS, do not purchase another Dodge one there are better aftermarket ones made.

I have no clue why going in and out of 4x4 seems to help other than coincidence.

rich

possible apps issue, but it sounds like the pcm is having problems, it controls the shifting. try having it reflashed and see what it does. Also if your charging system is not up to snuff it can cause shifting issues. Try driving it with the o/d off and see how it acts.

electromanj

Thanks. I'll try the apps reset and report back...

electromanj

I reset the apps and that took care of it until I shut the truck off. The 2 to 4 and 4 to 2 technique still works. Seems like everytime I have taken off the battery posts it is resetting something, and it shifts fine until I shut it off. The saga continues....

Edit*** I am a moron. Please disregard the statements about 2 to 4 wheel drive. It is the act of putting the transmission into park and then back into drive that causes it to shift correctly.

electromanj

Replaced all the battery terminals. They were pretty corroded, and replaced one battery. No change in shifting. However, I have discovered that I can "make it shift" by moving the lever to neutral and back into drive. I guess this is better than stopping to put into four wheel drive.

Any ideas where to go from here?

patdaly

Since the only thing not fully hydraulic on the RE is the Governor pressure circuit and the OD/TCLU, I would say that you have a wiring issue down at either the 7 pin connector at the trans, or something funky going on in the wiring down there. The Gov is not getting the correct pressure to shift right. The only theory that even makes sense is when you shift the TC, it wiggles the wires, and when you load and unload the trans going from D/Neut it does the same thing.

There really isn't much else that it can be.

electromanj

Thanks, I'll crawl under there and see what I can find.

electromanj

Still fighting this issue. Recently I lost overdrive. I have replaced the female connector to the transmission. I had a hard time getting the connector back on so I was thinking I had a bent pin on the transmission connector. I tried to use a little mirror to see it, but it is really hard to get to. I plugged it in as best I could and tested it. No progress. I then ordered a solenoid kit that has the governor solenoid, pressure sensor, 3-4 solenoid, speed sensor, and a new 3-4 accumulator spring. As the 3-4 solenoid has the male transmission connector as part of the harness, I won't have to figure out how to straighten the bent pin.

Here is where I am at now:

Removed the valve body and replaced all of the solenoids. I found that the 3-4 accumulator spring was broken and replaced it.

Question: When I removed the valve body, the accumulator piston dropped out along with the larger spring. I never saw the smaller spring drop. I have looked everywhere and can not locate it. My transmission has never been right since I got the truck. Is there any reason for removing the smaller spring from the accumulator piston, or perhaps somebody before me forgot to put it in? Where can I order a new spring?

The first picture is a shot of the spring I am missing. The second picture is of the pieces that I have. The last picture is of the broken 3-4 spring.

Thanks for any advice!
Travis.

electromanj

After some research on the web it looks some models don't have the smaller spring, so I threw it all back together. Overdrive is back, however it's still starting out in 2nd or 3rd. If I manually shift to first it does downshift. No more fault codes are present. Before I changed these parts there was a code. Can't remember the number, but the description was solenoid A. One of the 3-4 solenoids was open. Not sure which is which, but it was the one on the opposite side of where the main harness is zip tied to the solenoid frame.

dkenny

if you just an opinion..its in the tranny..the 2 to 4wheel change
doesn't matter..the 2 to 4 is in the transfer case not the tranny..
2 separate units. you might be looking a tranny rebuild.
good ones aren't cheap but worth the money if plan on keeping the truck
get it done be someone who know these trannys not a big chain shop.
I just had to have mine rebuilt..thankfully there was a guy local to me.
did a great job..I no longer have to wonder about my tranny.

-dkenny

electromanj

I am definitely looking at that by all of the metal pieces stuck to the pan magnet and everywhere else. Quite frankly I'm just glad to be able to grab 4th gear right now!
I am getting pretty close to getting my project truck
(F700 cummins powered of course!) road worthy. If I can get that done, I may be able to put this one on "injured reserve" for a while and get through the season.
This coming winter I plan to spend some quality time with my trucks....