My tranny started doing wierd stuff. When i go to accelerate i have to get up to about 1800 rpms before truck will start going if im on any kind of hill. It does it even when the truck is warmed up. So I took to a friends shop and he said that it read low tranny pressure. Is there a senor that needs to be change or will the bands do this if there loose, or is the tranny going bad, all other gears work and reverse is fine. My friend doesnt do tranny's so he didnt what to mess with it too much. My truck is a 05 2500, it has about 120,000 miles.

 

You may have fluid leaking by internally so you're having to get things moving faster than you should just to compensate for the fluid loss. Best bet is to take it to a respected tranny shop and have them check it.