Trans testing.......

[travelin_farmer]

Is there any tests that a mechanic can perform to check the health of your transmission? I have an 03 with the torqueshift and while driving if you let the truck coast (in gear) on level ground the truck will slow very quickly almost like the brakes are sticking... but when I bump the trans into neutral the truck will just coast with no restriction. Trans temps are normal but my fuel economy sucks...... just seams like I am dragging a 5k trailer everywhere I go.