Unfortunately the last couple weeks Old Reliable has been getting less reliable and more old, this time it hasn't been shifting into overdrive, but intermittently (the funnest kind of problems). I've gotten it to shift into overdrive by driving ~35mph and pressing the overdrive on/off button continuously but that doesn't always work and I have to 60mph 3,000rpm my way to work. It will shift fine when I get into town and drive at lower speeds and after I get to work it'll be fine the rest of the day. It only does this in the morning.
possibly unrelated but shifting from park/reverse into any forward gear will cause a clunk and the truck will lurch forwards a bit

Any help is appreciated, thanks

 

Getting any codes? If the PCM commands O/D, but, doesn't see the RPM drop, it *should* set a code...... If the PCM simply doesn't want to shift into overdrive...... need to find out why. Any issues with the speedometer? ABS? (if you have it....)

 

Sorry for the late reply, work has been hectic lately. I believe it has to be a wiring problem. I took it to O'Reilly's and asked them to test it but they, surprisingly, didn't have an OBD1 reader. They told me about the check engine flash codes and I went and did them a few times. The only codes I consistently got were 37 and 52 (I already know what's causing 52). Nothing to do with not shifting. I then tried unplugging the O/D Off/On button to see if it was stuck on, but that made no difference. Which means it almost has to be a wiring problem after the upshift sensor. It would have told me if the sensor was bad or if there was a problem with the transmission itself, which it didn't.
if anyone knows of anything else let me know, I don't want to spend $150 at a transmission shop for them to tell me nothing is wrong with my transmission, and I can do rewiring myself.

 

code 37 Transmission temperature sensor detected no temperature rise after start. **
or
Transmission temperature sensor voltage too low. **
or
Transmission temperature sensor voltage too high. **
or
Relationship between engine speed and vehicle speed indicates no torque converter clutch engagement. **
or
An open or shorted condition detected in the torque converter part throttle unlock solenoid control circuit. **
or
Park/Neutral switch stuck in park or stuck in gear. **

http://www.dakota-truck.net/CODES/codes.html

 

The code I found for 37 was Torque converter solenoid failure. Would a temp sensor effect shifting?

 

Trans temp sensor would. (supposedly) Lack of TCC might as well. Verify the wiring, if that's good, replace the solenoid set. (and fix the temp sensor....)

 

So I went to two auto parts store and asked for a trans temp sensor but neither could find one. I went to rock auto.com and auto value.com and neither of them could find it. I dug a bit deeper into error code 37 and found more than I had hoped for... It could be a Baro-Read solenoid shorted/bad, the part throttle unlock relay might be bad, or the torque converter solenoid is bad. This gives me a list of 4 things error code 37 could be and any one of them could kill my overdrive, but intermittently is the problem. I really don't want to take it to a shop so I really need some help figuring this out...

 

my 92 started doing that, especially with colder (cooler) weather, 1st year it never acted up if outside temps were above about 45. 2nd winter it got worse, would hold 3rd longer and more often. so I put a spare (fresh rebuild) in at 205K miles.... I think my OD clutches were just plain worn out. I still have that original trans, will rebuild it and keep it under the bench until I am done with these trucks..... probably not the last 1st gen Dakota I will ever own.... I am on my 5th one now.... (still own #4 and #5) spare that is now in Dakota #4, came out of #3, on which I converted into a stick. I still miss that one, still pi$$e$ me off that it got wrecked, and wrecked badly beyond repair. V8 clubcab, went like a raped ape when need be, and would get 20MPG without really trying.
I bought #3 and #5 with dead trannys. #5 was already pulled and laying in the bed of it when I bought the truck.... that one is 4wd AND an "RE" instead of an "RH" so I rebuilt its original and reinstalled it. that one was nowhere near as badly smoked as that one that came out of Dakota #3.