hey, with the truck in my sign, very very hard to start 4lo, and will choke mid track( need more power or tighter turbo?) , 3rd low will runn all the track loose at 42-300rpm, in 2 nd hi will start at 3500 and go down to 3000 in small class( 7500 lbs and 8500lbs) in 9500lbs or 10500lbs trun...