Transmission or Sensor issue?

[iann]

G'day,

I have some sort of issue with my 96' XJ and not quite sure as to what it is. When you hit 70/80 k's, there is a jerking motion and it seems like it's from the transmission. The RPM drops and climbs (slight drop 200 rpm) at 70/80 k's. It's like it's cutting in and out, however once I floor it to 100k's its not quite noticeable and cruises. I'm also thinking electrical, maybe air fuel sensor??? Coil??? dizzy???

What do you guys think???

It's not missing.
Transmission Fluid is full
Got oil


Cheers

[mtd]

unplug the transmission control unit and shift the auto box manually to see whether it is electrical or mechanical. If it shifts normally without slipping/jerking Just replaced my transmission which was grabbing/jerking and rpms going up and down. I had lost OD but the clutch packs were worn and needed a rest in my old unit.

[Roler]

One thing to check is if your TPS is still ok, since this is directly related to shifting characteristics. As you describe it, it occurs at a certain speed (see as certain throttle position) and not before and after. Check it to make sure that simple thing isnt the cause, before you start swapping out trannies.