I have the drive train, computer & wiring from a 96 Dakota in my old Dodge truck.
The auto trans (which I assume is a 46RH?) has around 48,000 original miles on it now. It had 44,000 when installed into the truck, and I've driven the truck about 4,000 miles since. The transmission was working great, but the original aluminum & plastic radiator started leaking. I've installed a new cross flow aluminum radiator with the trans cooler in it. I believe everything was working well, but the weather turned colder shortly after the radiator install (low teens for high temps). The truck gets driven little during the winter, and I need to drive it across town (about 3 miles) before it starts warming up operating temp with the 195 stat (pretty normal around here), so the trans fluid probably barely reaches 160 degrees until I turn around and come home. Its all in town, so things like OD or torque converter lockup are pretty hard to notice.

About a month after the radiator install, I blew a trans cooler line off, but didn't know it until I was almost across town and the trans started slipping. I stopped driving (more accurately it stopped moving) about a block later where it was the only place I could get off the street. I reattached the cooler line, and put in 8 quarts of ATF4 from the Oreilles that was walking distance from where I stopped. It started up and drove it home, where I added another quart of ATF4 to bring it up to full. The transmission seems to still shift very smoothly, but leaving a stop it seems to slip (feels like letting a clutch out) until it starts rolling, but then feel fine, but I don't think the OD has been working since.

Now that the weather is warming up, I'm driving the truck a lot more. I'm pretty sure the OD does not work. Last weekend, the temps were in the mid 40s. I started the truck cold, and drove it about a mile on the highway, then stopped for about an hour, the drove it about a 1/2 mile (highway) and turned onto a bypass where I drove the truck about 10 miles at between 65 and 70 mph. The (factory) tack reads 3,000 rpm at 70 mph, 3:55 gears, motor at operating temp.

When I ran it out of fluid, did kill the OD, OD switches or the clutches in the trans? The fluid still looks good.
What do I need to check and fix? I have not yet dropped the trans pan, if I need a solenoid or something I'd rather order that and have it here before dropping the pan. Ideas?
Thanks
Gene

Does your wiring still have the OBD port? If so, see what , if any codes you get.
1996; is that OBD 1 or 2?

1996 should be OBD 2 and have the electronic 46RE transmission. I'm not sure what the cause of your issue is but running it dry till it stops in never good for an auto. A scan tool with full diagnostic capabilities might give some insight to operations provided the OBD port is still in the harness.

The port is still in the harness, my buddy has a full read scanner, but he was too busy to get to it this afternoon. We were discussing if it was OBD 1 or OBD 2. I thought the 46RE started in 97.

Running it out of fluid sure wasn't in the plan. I was unaware it blew the line off until the trans slipped the first time. I was cruising along at 30 mph and hit a hill before the trans first showed any sign of an issue, and I pulled over as soon as I could. Truthfully, I was pretty happy that it still moved after I added the fluid. It wasn't until I was driving it home that I saw the trail of ATF on the ground. When I saw where it started to dump the fluid, I was pretty surprised it went as far as it did.
Thanks guys, I'll post what we find out.

What is your "old Dodge truck? You may want to drop the pan and look for any obvious issues. You can always run a pressure test to see what is what. If you have the "check engine light" hooked up you can do the key dance to get codes.

https://www.allpar.com/threads/the-1980s-1990s-chrysler-computer-codes.229009/#post-1085223107

Pressure test is on the last page...
https://www.trucktransdiag.com/downloads/technical-data-for-dodge-transmissions.pdf

There is a build thread here on Moparts, in the street rod section: "49 Dodge pickup on a 96 Dakota 4x4 chassis." See pic below.

i used the entire drive train and wiring harness from a 44,000 mile 96 Dakota 4x4. Everything is intact from that Dakota pickup I pulled everything out of (the bottom half of the frame was rotted away).
My buddy has a full range scanner, but it will be mid week (this week) before he can get to it to make the scan. I'd rather have an idea what to expect, if possible, before I just drop the pan and have a look. Ordering parts online myself to have on hand costs about 1/2 of what things cost to have someone else order them online here locally The truck is still transportation for another couple of weeks. Gene

94 was the first year for OBD II and 96 was the first year for the RE..

Nope 96 was 1st obd-2. My 94s were still obd-1.

Not sure if the same, but on my '96 Ram I have both the OBDII under dash and the Chrysler diagnostic connector under the hood. Most times I have to use the Chrysler connector with any decent scan tool to read powertrain values or even accurate DTCs. In my opinion, OBDII had very limited ability that year.

The wiring on this truck has whatever Dodge gave that 96 Dakota from the factory, nothing has been altered. I know it has the under dash connection, and I wouldn't be surprised if there wasn't another connection under the hood (I just don't remember). The scanner my buddy has is a full scale scanner that he buys updates for each year. His isn't some piece of junk you pickup at HF or Autozone.

I also understand that the early OBD2 didn't have all the abilities of the newer stuff, but at this point, all I need it to do is determine if the electronics inside the trans are functioning as Dodge made them to function. Hopefully tomorrow or Thursday we can get it connected to the scanner.
If the weather cooperates, after Friday I can drive the coupe as transportation, so I can get the truck fixed. At this point, the only sure thing the truck trans is missing is the OD.

So a 1996 has an Chrysler style OBD-I connector under the hood by the PCM computer
plus an OBD-II plug under the dash?

Update:
To answer a few questions, the 96 Dakota has the plug for the scanner under the dash, I did not look to see if there was a connecter under the hood. It is OBD2.
I got 3 codes:
P1765 Relay control
P0711 Fluid temp sensor
P0748 Governor pressure solenoid circuit.
According to google, all could have been tripped by low fluid, guess that makes sense, I ran it out of ATF-4 the day the cooler line blew off.
We have reset the computer and I will drive the truck a couple days and we will see what comes back, we will address what we have then, unless you guys have a better plan. Gene

I hope it's that simple...and it sounds plausible. Yeah, let us know...

sounds like the solenoid pack... comes with gov solenoid and torque converter solenoid. not taht hard to change.
Sonnax (among others) used to have a kit to repair the governor solenoid.... there's a screen within that plugs up as I remember, the kit I remember (not that you need that many) came with enough to do 10 of them, but a new solenoid isn't terribly expensive.

It would probably be a good idea to price out the solenoid pack and find out how long it will take to get one here. I think I replaced the solenoid pack in that trans that was in my 39 I tried to save that didn't work.

You are correct, my mistake.

There isn't a solenoid pack, there is a solenoid and a transducer, they should be replaced together.

Thank you. The one time deal with the 39 was a couple years ago, the old memory isn't so good anymore.

ok... not a solenoid "pack" as in like what an A604 would have had.... just 2 solenoids involved in a 44/46/47 RE, but still sold as a pair, bundled together in 1 box...... I don't think they are available seperate. I've always bought them as 1 part. Not that expensive and not that tough to put in but you do have to drop the pan.

I had a chance to look over the electrical end of things outside of the pan this afternoon, the wiring and connectors on this harness is all very clean. I'm also pretty sure the only things I'm missing are the OD and converter lock up. The truck has a factory tach, according to it, I'm doing about 1300 rpm @ 35 mph, and 2500 at 55 mph, the truck has 3:55 gears with 235/75/15 tires, so I believe its at least shifting into 3rd. It used to run 2500-2700 at 75 mph. Now 70 mph is 3500 rpm.
The trans shifts so smoothly, you really have to be paying attention to tell if it shifts, but you can see the tach drop around 25 mph. I haven't been over to see my buddy to see if the codes have come back, but OD still isn't working, so I expect the next step is the solenoid and transducer. Will change the filter and adjust the bands while the pan is off. Might even put a drain plug in the pan. I intend to make this the last truck I will need.

I don't recall ever replacing a governor solenoid for a no O/D, L/U condition alone. That is more likely to be a faulty reading sensor like VSS, TPS, CTS or something of that order. There are two solenoids, one each for L/U and O/D that have a single ignition hot supply wire and two separate grounds that the PCM grounds. I would look for 12 volts there before going any further.

You might be thinking about the L/U and O/D solenoids, those come as a pair and are separate from the governor solenoid and pressure transducer.

OK, I was a bit confused before, but now I'm really confused.

Where are the LU and the OD solenoids located on the trans itself? While I'm asking dumb questions, where does that 12 volt power source come from, and can I check that out from above? This is a 4x4 trans in a Dakota chassis, I will have to put the truck on a rack to check pretty much anything under the truck. I'd rather have the parts in hand when I get the my buddy's hoist, the same parts locally are 2x what they cost online.

I thought the changeable parts on the valve body were the governor solenoid and transducer. I don't remember seeing any other solenoids inside of the pan.

They are on the valve body. They are hard wired to the external connector. I am unsure where the 12 volts come from or what the wire color is but it should be 12 volts key on. I would imagine it comes out of the engine compartment junction box. Look up torque converter clutch solenoid on rock auto or something like that.

OK thank you.
I did follow the wire harness from the trans connector up to the connector into the main harness. I should be able to make sure that at least one of those wires has 12 volts.

You should have a relay in the power box in the engine compartment. Note that the PCM controls both a ground to turn on the relay and to engage LU and OD.

This has the small Dakota under hood power box (about 5" square), there is no relay marked for anything trans related (relay for: ASD, starter, blower motor, anti lock brakes, cooling fan, and headlights), are the only relays and there are 4 fuses.

look at the underside of relay box cover. legend for what's in the box is there.
I'm guessing its the solenoid on the valve body causing your issue. that gov solenoid was known for issues in certain years.
Oh just thought of 1 other thing
There is a spring on the valve body, has a cover over it with 2 bolts, a "3-4 shift spring". I've . found a few of those busted over the years. Including on my own 96 Dakota 4wd back when I rebuilt that trans 70k miles ago.

I looked at the legend under the cover for anything trans related, didn't see anything. I did trace the wires from the trans up, I will check for 12 volts on one of those wires when I can get the truck up in the air, on jack stands I can't get my arms into position to unclip the wire connections.
I will order the LU & the OD solenoids. While the pan is off, I will examine everything in there. Unfortunately, that it is at least a couple weeks out right now, life is about to get in the way. The good thing is, as long as the weather doesn't turn to real crap again, I'm driving the coupe, the truck can sit.

as i recall?,there is a way to check the solenoids at the trans,check for 12 volts and ground the right pins and you should hear a click inside the pan there may be a youtube video about it?

I've been pretty distracted from the truck for the last few weeks and haven't even had a chance to look it it at all. Since I'm driving my coupe, the truck has just been sitting in my garage. If the weather ever warms up, body work is coming.

This morning I was showing the truck to my grandson and noticed (and remembered) the truck has the dash button to shut off the OD. Just for kicks, I gave the button a push, and it really doesn't feel like it is doing anything at all. I thought they were suppose to be spring loaded, so I poked it a couple more times, and it really doesn't look or feel like its functioning at all. This new reevaluation brings up a few questions.

Am I correct in assuming that button could be the source of my no OD problem?

Would that button switch be a normally open, or a normally closed switch?

Can I just unplug the wires from the switch, or do I need to jump the switch to make sure the OD is activated?

The truck sits low, and even on jack stands I can't get into position to disconnect the wire connector to the transmission to test for power. I would have to take the truck to my buddies and use his hoist, which was going to be the next step until I saw the OD button on the dash.
I see no reason I would need to shut off the OD on this truck, any towing it might ever be used for would be pretty light duty. It wouldn't bother me at all to remove the switch from the dash. Gene

It's a momentary switch that just tells the PCM to turn off the O/D. It resets with every key cycle.

So as long as power is going through the switch, that probably isn't my problem? Darned.
I've pulled the switch, there seems to be continuity between the blue (ign hot) and the green/orange tracer until the button is pushed. Then there is the momentary break in continuity, but the switch is pretty flaky and it doesn't always break the continuity.
If I connect the blue wire with the green/orange tracer wire I should be able to eliminate the switch, correct? Probably won't help my problem, but would at least eliminate a flakey switch and make me feel better.

I have an 87 Dakota factory service manual, and an 87-96 Haynes repair book, but neither cover this switch. The problem with the factory service manuals through these years is the manual only covers the things that changed that one year. If you don't pick the right year the change occurred, its not covered in the later manuals. Is there a general repair manual (or probably even more helpful a book covering the wiring diagrams) that would cover Dakota trucks from 90 to 96 a guy could buy?

i have a 96 fsm for full size trucks that i could be persuaded to part with

I have a 97 full size Ram FSM on CD, but the Dakota wiring is Dakota only until 98, then it includes the Durango as well, but that is the next gen Dakota and I'm pretty sure the wiring changed by the Durango time.

i also have a 92 Dakota FSM,its OBD1 so most likely different,if i was smart enough i could scan the circuit you need and email it to you,but 96 is OBD2!!

The 92 probably won't help much, but its probably better then the 87 I have, in 87 everything was sill carbed.
The generic Haynes book has the efi wiring for the V6 & the V8, but it doesn't show this switch anywhere.

The switch has 5 wires.
One blue ign hot, and one green W orange tracer that has continuity unless the button is pushed. Then most of the time (but not always) it looses continuity only while the button is pushed.
There is an orange wire that is hot when the lights are on, it has continued continuity with a black wire all the time. The switch has a light in it, I would assume those wires are for that light which is probably a dash light. The switch also has a light I assume is for when the button is pushed and the dash lights are on to indicate the button is being pushed, because there is also an orange w white tracer wire that has continuity with the orange & black wire only when the button is pushed.

If I don't hear any different, I think I'm going to splice the blue wire and the green w orange tracer wire together and remove the switch all together. That probably won't help my no OD problem, but at least it eliminates a flaky switch I don't need.