I have a question about a problem I just started having. I have a 1996 4x4 dodge and when its cold it shifts fine but it seems when it warms up it shifts funny and you have to be doing 50- 55 mph for it to shift into high gear. I went to auto zone to get a temperature sending unit for the transmission but they sold me the wrong one or Im looking at the wrong sending unit on my truck. Is it located at the rear of the transmission. Also they said I have a 0123 code showing up so how do I fix that too. I know its the TPS but can it be fixed.

 

There is a bunch of info on the TPS on this site from adjustment to drilling a hole in it and spraying it out with electrical cleaner. Do a search and you will have plenty to read....

I have a thread started on transmission troubles as well...be glad yours at least goes into OD...I think you will get that problem resolved easier than mine....