I have an 03 ram 2500 with a 4 speed auto.

The truck has 170 k and it has started to shift differently lately.

I have dropped the pan, changed the filter and refilled it with ATF + 4.

The motor will get up to 2500 plus rpm before it will up shift where before it was smooth shifting at around 2000 rpm.

1 st and 2nd seem to shift ok and overdrive is coming on.

Does anybody have any suggestions. If I did need a whole new transmission, can anyone recommend the best place to start looking? Or perhaps! I should take it to the mechanic. I just know dodge will charge me big time.

Thanks,