Engine/Transmission (1994 - 1998) Automatic Trans

[Jschafer]

I am having erratic shifting on my 94



This is how I believe it works but would like to be sure for diagnostics.



The 2,3,4 shifts are controlled by the tv cable and the governor wich is electric and the tc lock up is controlled by the tps.



The problem started with the tc locking and un-locking so for the trip I just kept it locked with my mystery switch, now the shifting up and down is erratic but all gears are solid and I drove it home from New York this way, fluid is fine. 1-2 shift and 2-3 seem to be ok Some times it shift up fine other times it shifts at a reel high rpm into 4th. sometimes you just touch the gas pedal and it down shifts. I checked the tv cable it is ok and I cleaned the tps I have only driven it a bit since cleaning and it, worked ok but I have to leave again monday afternoon and I want to make sure I am not missing something. I will be testing it this afternoon to see how it is acting but I don't have much time.

Thanx in advance

Joe

 

[fox]

Do a search, but I think you will find the answer is ---clean or replace the TPS.

 

[Joe G.]

The transmission in your '94 is a 47RH not a 47RE. The RE was used in the '96 and later trucks. The 1 - 2 - 3 shifts are controlled by a fly weight governor not an electronic governor like in later trucks. Electronic controller boxes like the DTT Smart Controller won't work on your trans. The OD (4th) shift and TC clutch lockup are controlled by the PCM. Your TPS probably is dirty so hose it down with contact cleaner and work the linkage back and forth to clean it. If that doesn't do it then you may have to relace the TPS. You may want to look at this thread:

https://www.turbodieselregister.com/forums/showthread.php?t=128962

 

[Jschafer]

Thanks Joe

I am glad you explained it, as I was wrong on the 4th gear(OD) shift and the governor



I pulled the tps apart yesterday and cleaned it real good then put some dielectric grease in a sealed back up. when I installed it I had 1. 2 at idle position and 3. 4 at wot (I have mine slotted for adjustment) I think those are close to what it is supposed to be. Also picked up a new trans temp sensor this am just incase.

Joe