Hey i have a 93 dakota 4X4 auto.
I was driving up the free way and as i accelerated the trans didnt shift in to 4th so i as doing 60at 3000Rmp. Any help is welcome.

 

Mine wouldnt shift in to 4th and i dont know what trans i have how can i find out.

 

It could be a bad speed sensor to wiring problems probably a bad fuse. Check all.
You will have a 46rh.

 

sorry to thread jack, but mine is doing the same. someone had mentioned here before that it could be the tranny filter. well the code for the OD solenoid came up a while ago, did a tranny filter kit in hopes i could skip by it, but to no avail. Now what i am wondering is where is the solenoid? I know its in the pan somewhere, but is it easily accessible? Mine is also the 42-rh, in my 93 v6 2WD. Sold the 93 v8, body was too rotten. Bought a 99 alero v6, gave it to the gf, and took my old dakota back (for those who remember who I am).

 

Im thinking its something to do with the shift solenoid were is it and is it a fairly easy fix. im planning to take it to my local trans shop, they do free diagnosis, see what they have to say. what other issues are common on the 42rh trans mine has 116000 miles

 

I have the same problem, mine wont shift into o/d, i replace the speed sensor and still nothing and checked the wiring no breaks or anything, any suggestions its a 91 4x4 auto

 

I see a pattern here. Guess what mine won't do. I got codes out the a$$. 21 45 37 43

 

Update: I'm slowly tracking the problem down. As I was just in the tranny pan a few weeks ago doing a tranny filter change, I took a look at my solenoid and all the wiring inside of the pan and all was good. Everything looked brand new in there almost. After I got the pan back up and everything, I took the 3 pronged connector apart and cleaned it up. Still no o/d. When I'm on the highway doing 100 km/h, and I hit a decent sized bump, it sometimes will shift into o/d, not all the time tho. Crazy4x4RT has mentioned before about the coolant temperature sensor being faulty causing this problem. My problem is looking more like the wiring is the problem and not the actual sensor. I'm going to be tearing into the truck today after my morning coffee to see if I can track it down to that sensor or not. We will see what happens and I will let you guys know!

 

My '93 3.9L does the same thing, but most of the time it works fine. Occaisionally, it will want to hold in 3rd gear. Not enough to be bothersome, but I have noticed it doing this.

 

Ok finally got some time to really look at the truck. it gave me 3 codes 12, 15, 55. according to the FAQ1 12 and 55 are normal while 15 is no signal from Vehicle speed sensor. Im thinking i need to replace the sensor im going to check the connections first and test the sensor befor i buy i new one. has anyone ever changed the speed sensor on there truck and if so is it easy and do you have any tips.