I've noticed every time I try to accelerate slow, trying not to get rpms higher than like 1400, the transmission seems to have problems deciding which gear it wants to be in. Is this normal? For my truck to accelerate and shift smoothly the rpms have to be at least 1600.

 

It's normal. Or should I say they all do it. It is all tied into the throttle position sensor. I just make sure I am not at that rpm when I take off.