I have stock automatic transmission. The car switches gear from say park to reverse or drive or any of the other combinations fine and when accelerating the car gets through first gear with no problem even with the hammer down however when going into second or third the rpms begin to waiver moving back and forth and unless I ease up on the gas the car refuses to shift. Even then I feel a significant loss of power. My transmission fluid level is fine and has been recently changed out with some lucas stop slip additive. Is this the result of a bad filter? A bad solenoid? I’m at a loss and will be bringing it to my usual mechanic next week when he returns from vacation however I’d prefer to handle this myself.

 

Why was Lucas introduced? Was it a preventative measure or an attempt to fix something?

 

Preventative but with the way it's running im thinking its the solenoid. While i have the pan down tomorrow I'll be replacing the filter and obviously putting in new fluid without the lucas so it doesn't through off the viscosity.

 

And of course testing and if need be replacing that solenoid