2004 Ford Escape transmission?

I have a 2004 Ford Escape XLT, auto,V-6, with 129000 miles on it. It runs fine except for a couple of things. One is, at highway speeds the transmission will seem to shift up and down. Also sometimes at highway speeds I get what I describe as a “bump” or “shudder” I think it is coming from the transmission. Any clues?
-Dave

What makes you say that it seems that transmission seems to shift up and down? Are you going by RPMs? Or something else.

At highway speeds a feeling of transmission up & down plus occasional shudder leads me to think of a torque converter lockup problem.

But these kinds of things can come from entirely different stuff - like old spark plugs & wires, fuel delivery issues, various sensor problems…

Any warning lights showing up on the dash?
What is you history in terms of transmission maintenance?
Have you at least checked the transmission fluid?
Other maintenance? (plugs, wires, filters…)

I’m in agreement with cigroller about the possibility of non-transmission related things causing this and the possibility of a converter problem.

These things are pretty touchy about fluid anymore so if the transmission has never been serviced there’s a possibility that a fluid change could correct this; assuming it’s actually related to the transmission.

You might also get the vehicle scanned for codes. Most chain type auto parts houses will do this for you free although I think this is not allowed now in CA and Hawaii.

The fluid level is fine. The fluid has never been changed, at least as long as I have had it(three years)
It’s the rpms going up and down that leads me to feel like it is shifting. I guess another way to describe the shudder is like driving over rumble strips at highway speed.
The plugs or wires also have not been changed.
Would you think new plugs and wires would solve it. It runs smoothly and does not miss. Would a trans. Fluid change help?

Your V6 motor has coils on plugs and you could be getting a misfire without showing a code. If you can’t document new plugs in the history of the vehicle, then new plugs can’t hurt. A transmission change of fluid (not a flush) would be a good idea too.

It seems the vehicle is getting minimum maintenance. A '04 is due for new coolant, brake fluid change, and differential(s)/transfer case fluid changes too. If none of these things has ever been done then vehicle is overdue for preventive maintenance.