A long story short, i had to get the tranny rebuilt with 36,000 miles. Another story, another time. Anyway the mech put an updated shift kit in the truck and i can belive the difference. For the first time in 7 years, i actually got 15 mpg. What a difference. I noticed the tach doesn't go above 2500 rpm's even at a higher than legal speed. I love it!!!!!!!!!!!!!!!!!!!!