The truck has 157000 miles on it. 4in lift atlas 40 Ficm 40 HP SCT canned tune. Everything else is stock. Truck though the code P0755 shift solenoid b malfunction. Tow haul light flashes. When putting truck into D it slams into gear. When placed into R it shifts fine but the motor boags down and rpms raise slightly. When driving and slowing down at 10mph the gears slam. I replaced solenoid ( overdrive clutch SSPC-B) today along with trans filter and new fluid. Still has the same problem as before tow haul still flashes.