at 40 mph i have a vibration when I excelerate up small incline
If I had this symptom during acceleration, I would first take a look at the driveshaft U-joint(s).
If this truck has an automatic transmission, another possibility would be a problem with the torque converter lockup mechanism.
My 08 Tacoma 4cyl would vibrate on coming to a stop when cold. A life long friend and mechanic said to change the tranny fluid at least every other oil change. The problem went away. The real cure is to replace the tranny filter and continue with fluid change on a regular schedule.