Hi, a friend of mine has a 98 Dakota with an automatic. The overdrive is not working and he wants to bypass The ECU on it and just use a toggle switch like I did on my '93. I have heard that the wiring is different on trucks newer than 93 so I can't tell him how it works. Does anybody have a wiring diagram or instructions on how to do it with the '98 models? Thanks, Joel

Not sure if that can be done on an OD newer than 95? All of the newer ones are controlled by the TCM in the computers. What engine is in his Dakota? If it's a 4.7, it is an entirely different transmission than a 518 or 46RH in the older trucks. I'm not sure when they stopped the 5.2 & 5.9 Magnums in Dakotas and Durangos, but those would have had a 42RE or a 46RE in them. The 4.7 vehicles had a 545RFE. Maybe some of the guys on here who know and work on transmissions will chime in.

I assumed it was a 318, but I'll have to ask him.

No 4.7 in 98.
I have a schematic, but I have to leave in a few, but I can get tomorrow am.
hth

Awesome, thanks!

Here.
I hope you can bypass the PCM because the OD circuit also locks the convertor. You may have to tape over the CEL

OD is still controlled by a solenoid so controlling it with a toggle switch shouldn't be an issue. Same with lockup, the diesel guys have been controlling the Lockup with a switch on the RE's forever ... All he has to do is switch ground .

I always read the RE has a digital code needed, not just grounding the pins like the RH?
Would have gotten a RE if that were the case instead of the 518 when I did the swap.
I know there are controllers for the RE available.

I'm looking at the pages provided above and it doesn't look that way for OD and lockup anyway ?? The RE needs digital for the gov pressure circuit , on my 2000 ram I put a resistor on the line to the PCM (BCM?) to fool the gov pressure circuit to not see the increased pressures , that worked perfect for over 200K miles ...

Correct. On the RE, the computer controls the governor pressure (trying to get ~1psi/mph, then the valves in the transmission control shift points off of that).

Lockup & OD are still solenoids that can be triggered externally. Computer may not like it though

Thanks for the help.
With this being a '98, would it have the RE, with the computer control of more than just the lock-up and OD?

Round black connector in the case = RE.

White oval connector in the case = RH. (The hole in the case is round but the connector top is oval).

Isn't easier than that?

RE = 5 pins
RH = 3 pins

The RE has a 3 prong connecter the RH has a 2 prong connecter

RE has LOTS of wires, RH has 3 ,, center one is + one outer is lock up, the other outer is OD

RE has 8 PINS.

RH has either 2 or 3 PINS. 2 for non LU and 3 with LU.

98 should be RE , they started either 95 or 96 ...

He brought the truck over today and I went under and looked at it. He said the engine is a 318, but the original transmission was bad and one was swapped in out of a 93 he thinks. Also the wires are bare, as you can see in the picture, and they were touching. So I separated them out.
So one of these gets grounded to activate the overdrive, right? The brown green one? Or does it get 12 volt positive supplied to it? And then apparently the black one activates the lockup converter. If it's really a 93 transmission, does it even have lockup capability?
Thanks a lot, Joel

You know, the part number stamped on the case would tell you exactly what it was then you wouldn't have to guess.

i was under the assumption those transmissions used the new style plastic pan gasket with the imprinted seal stuff on it, so as to be reusable ?