Engine/Transmission (1994 - 1998) PCM for auto vs. 5-speed

[BigPapa]

I'm converting my 1995 2WD auto to a 5-speed. The donor truck is an identical 1994 with a 5-speed. I'm getting conflicting reports as to whether or not my PCM(for an auto) will work with the 5-speed. One person told me no problems, someone else told me it will work but the cruise will not, and another has told me it will not work at all. Does anyone know DEFINITELY where I'm at with this?



Thanks!

 

[Howard Durand]

I doubt if you would have much trouble converting from auto to manual.

My 94 Service Manual shows only one wiring diagram for the PCM. It does not differentiate between auto and manual transmissions.

Since you are dealing with the 94/95 trucks, the auto transmission is a 47RH which is not as electronically dependent as the later models.

You will no longer have to deal with the Throttle Position and Transmission Temperature sensors which directly affect OD and TC opertation. I think they can just be disconnected without removing the wiring itself.

There are a few differences in the wiring to accomodate the auto transmission that may have to be changed but, if you have a service manual, they can be pretty easily identified.

You may have to have the PCM re programmed for the manual. A "good" DC shop manager should be able to help you with that information.

 

[mfunderburgh]

Your auto PCM will work just fine. My cruise works just fine also. Just leave the wires that hook to your transmission undone. The park/neutral safety switch will either need to be hooked up to the clutch pedal or you can just cut the end off and wire the two wires together. For safety its probably best to just take the time and run some wire to the clutch pedal. Matt

 

[BigPapa]

Thanks!

Thanks for the replies gentlemen!



Scott