GMC Truck Transmission Not Shifting

Truck Shifts Ok When Cold. When Warmed Up It Will Not Go Into Overdrive Or Gear One. I Have Already Changed The Electrical Harness And It...

Can You Please Help- Truck Is Not Downshifting- From No Gear. We Have Replaced The Two Shift Solenoids And Replaced Fluid And Filter. Still...

When I Drive Up A Hill Or Need To Downshift To Accelerate My Truck Runs Rough The Tach Jumps Around 2,000rpm And Makes A Bogging Sound, I...