Help! 01 Pathfinder - Skipping Gears...?

[JunkIt]

Hey All,

If anyone has any advice or experience on the following problem, please let me know - here it is:

I have a 2001 Pathfinder (3.5 V6) with 178K on it so it's getting up there. I've noticed over the past two years that it has lost some pickup on the highway whereas it used to be able to accelerate rather well when passing or going up hill. Some other things that I've noticed:
- When I put the pedal down, the car downshifts but I think it is skipping a gear since the rpm's go from about 2800 to over 4000 (normally it would go to about 3300 or so)
- The problem seems to persist more frequently when the car is cold - if I've driven it recently and the engine is warm, it tends to drive like normal and have better acceleration and shifting
- There is no knocking or pinging from the engine.
- There have been no check engine lights or other indicators.
- I've changed air and fuel filters and have had the transmission serviced within the last year and change the oil every 3000-4000 miles.
- I cleaned the mass airflow sensor earlier this week although it didn't look too dirty. The problem is still there.
- I've put SeaFoam (engine and injector cleaner) in my gas but haven't had the guts to put it in my crankcase or the intake manifold like the bottle suggests.

Please let me know if you have any suggestions as to what could be causing this. I'm thinking that it may be electrical or software related but am concerned that there may be a larger [and more expensive] transmission problem. I've also been told that certain types of transmission fluids cause valve sticking in these models and that thinner fluids may work better... servicing the transmission will probably be my next move unless I hear some other advice.

Thanks!

[corman1982]

hey man i have the same problem. Did you ever get it fixed?