i have a 6.0 and 4l80e from an 01 chevy truck,in my 55 chevy, useing the truck harness,my problem is after driveing for 30 min or so my tranny acts like it goes into tow/haul mode if you pull over and shut off wait a few min it's fine for another 30 or so then act like it goes to tow/haul mode again any help would be greatly appreciated, thanks