Was having tranny issues that seemed to be related to a low fluid situation in my '94 XLT, 4.0L with 109K miles. After adding nearly 2 quarts of the correct Mercon fluid, I thought the problems were over. But today things acted up again only a little different. It seems to surge then slow, surge then slow when just beginning to move - even tho my foot was steady on the gas. I put it in Neutral and it revved normally so my thoughts shifted to the tranny. I managed to drive the 2-3 miles home and changed from O/D to D at red lites - and even shifting to 1 when between lites - with things still acting badly. I heard some rumbling sounds from underneath at times. And I swear the speedo was registering much faster then my actual speed. (?!) I shifted to 4wd for a short time too.

So I read thru lots of Forum posts and come away with no exact matches for this problem. I did read 1 or 2 that said there are speedo sensors (or something) located in some model's tranny's. That flushing is a no-no. Draining & re-filling and a new filter might help. That Aamco sucks. I'll be taking it to a mechanic 'coz I'm not gonna fool with it. Meantime, if anyone reading this has some helpful comments, I'd love to hear them. Comments that describe cheaper fixes than a major rebuild are the most welcome!!!

 

The 1994 was the last year to have a cable for the speedometer AND a VSS(vehicle speed sensor) for the Computer(controls trans), cruise control and ABS.

If you look on the trans for the speedo cable you will see the VSS sensor with it(two wires), they are both connect to one unit.
Since speedo is acting up the VSS may be as well, which would confuse computer for when to shift trans up and down.
It could be the gear on the cable/VSS unit or the speedo cable is binding up and releasing which could also effect VSS.
Pull unit out of the trans and also disconnect speedo cable from it.
Check gear and check speedo cable(you can use a drill on speedo cable to run it up to speed and see if it is binding, may need to be a reversible drill can remember which way it will turn)

 

Thanks RonD. Could you also read my latest post "Big Driveline Problem PLs Help!!!" that I just posted? Things have gotten waaaay worse since I wrote this post yesterday.Thanks!