My auto transmission with 8,000 miles on it is taking a long time on full throttle upshifts. My truck will upshift @ 3200RM on 1-2 upshifts, but the motor will float there & power will die off the nose of the truck dives down then it shifts. The 2-3 shift happens @ 3100RPM, & does the same thing, but to lesser degree. Could my filter be clogged already???