[Pablo1]

I have a 99 ford expedition 5.4L with 140k miles, recently I noticed that when I accelerate the car the RPMs will go up but the car won't pick up any speed, I noticed this and I put on a new air filter, cleaned the MAF sensor and the throttle body, went for a test drive and it keeps doing the same, there is no check engine light, there's no missed fires or anything weird, thanks for reading any info is much appreciated

 

[Action]

Sounds like the transmission is slipping.
Check and smell the tranmission fluid.
Post back with the results

Action

 

[TBIRD430]

When was the transmission serviced last???