Engine/Transmission (1994 - 1998) Transmission

[JamesPhillips]

Hello all. I posted some threads last year regarding transmission troubles. I ended up having it rebuilt and it's been doing great until now. I have a 96 2500 ext. cab, long bed, 2wd with an automatic transmission. At around 122K, it was not shifting properly and the Dodge dealer rebuilt it for me. $2000 later, I was back in service. I currently have around 138K on the truck and it's beginning to act up again. What is happening is that between 40 and 50 mph, it's seems that overdrive and 3rd gear are fighting with each other. I can hold the accelerator steady and under a slight load (small hill), it will switch back and forth between OD and 3rd gear constantly. Any ideas or further questions? Thanks, James

 

[vssman]

Sounds like a TPS (throttle position sensor) problem. Do a search on tps and give yourself some time to read all of the info.

 

[Missouri Mule]

I agee with vssman check your TPS( throttle position sensor) it mite need cleaning.

 

[ndurbin]

defintely sounds like the TPS. A bad TPS can screw your transmission up pretty good. Try cleaning it and rewiring it (do a search and you'll find all you need). If that doesn't work replace it.

 

[Dfuruness]

I think it is the TPS as well. I had the same problems. I replaced the TPS and no more trouble. You might want to check the threads for cleaning the TPS. I have not tried it myself, however, lots of guys say it works wonders.



Don

 

[JamesPhillips]

Thanks everyone. I agree that it's probably the TPS. I looked closely at it last night and didn't see how it could be cleaned. I also searched the threads and didn't see a way to clean this, though I may have overlooked something. I checked on a replacement and it looks to be about $200. Does anyone have concerns with getting one from a parts house like Advance or Autozone or is this something I should get from the dealer.

 

[Howard Durand]

James,



Your problem is probably caused by electrical noise picked up by the TPS wiring.

To eliminate this, the wires that carry the TPS voltage and signal to and from the PCM need to be removed from the wiring harness.



Before you spend $200 or so on a new TPS, locate "shendren" (Scott Hendren) who posts here frequently and also has an ad in the Classifieds.

He has made up an inexpensive rewiring kit that will eliminate TPS problems originating in the wiring harness.



You also may want to check the throttle cable and adjustments. Have they been replaced under recall? If not, they may be getting worn.

 

[JamesPhillips]

Repair is complete

Thanks everyone for the thoughts and suggestions. I purchased the wiring kit from SHENDREN and made the repair this past weekend. I've driven the truck about 100 miles and the problem seems to be corrected. If you're having problems with hunting between overdrive and 3rd gears between 40 and 50 mph, it's worth the $39 to try this first before spending $200+ on a TPS.

 

[Howard Durand]

James,



Glad you got the problem solved. Scott's kit is the best way I

know of to totally eliminate the noise problems encountered in the TPS circuitry.

My 94 has never given me any trouble. One reason, I believe, is that the 94 and maybe the 95's have a dedicated 5 volt line from the PCM to the TPS.

I think that later models feed both the TPS and the Engine Speed Sensor with the same line.

That added exposure could be the cause of so much trouble.

Cutting the TPS loose and feeding it through a separate, shielded wire is a lot easier than ripping open the harness.