When I am driving down the road and let off the gas, the truck doesn't drop to idle, it drops about half way to 3/4 of the way there. If I am slowing down it will not fully drop to idle (750rpm) and I am going slower than 10 mph. Is this normal? I am almost positive that this did not do this when I bought it only a few months ago.

 

it sounds normal, these electronic engines also need some time to recalibrate the gauges. the truck doesnt drop to idle persay when pedal is released. the torque converter unlocks. u still have some engine to transmission coupling to result in higher then idle reading.