qx4 hesitation, slugglish engine revs loud but seems like its not going anywhere

[infinitiwon]

My 2001 qx4 sometimes accelerates horrible not off the line but at the end of first gear going into second. engine revs loud but seems like it does move until it shifts into next gear????????????? any suggestions i have changed fuel filter, plugs, o2 sensors,i use mobil one syn, i use 93 octane dont know what else to do anybody have same problem or solution???????????????????????

[frapjap]

It sounds as if the torque converter or transmission is slipping. Add some Lucas Slip Fix from the auto parts store to confirm. If it gets better (slightly) then you have a transmission problem.

[Buzzman]

I have to agree. From your description, it doesn't sound like an engine problem. Transmission would be my first guess.