ok git a guy a work that is having issues with is 00 f250 7.3l has the auto tranny 4x4 with a 10" lift and 37's stock truck other than a super chips tuner. he said that when he is driving its like someone is hitting the breaks momentarily and the truck lugs then it goes away he said the it happens about every 20 secs or so but under 20mph it doesnt do it any ideas to this issue? Tranny?