I put a spartan on my 09 F250 with 5,000 miles on it, i now have 18,000 I run the 250 tune as dd. truck has never show any problems untill recently. when cruising slow (school zones) 20-25 mph eveything is fine but accelerating gradually its like it slams into second then back to third then slaming back to second all in a matter of 3 seconds and i let off. It only does it every now and again but still has me worried. This is when the truck is warmed up not cold. Anybody else had this problem. I already added the extra quart of tranny fluid.