[White70C20]

Originally Posted by BrianG

Agreed, that's a lot of rpms for 55 mph. I'd check the gear ratio. You might not want to go with too high of a gear depending on what your tire size is, and how you normally drive it (city/highway). you want to get into the right rpm range for your engine and your style of driving. 5 mpg is pretty bad, but a lot of factors can contribute to that. It does sound like your gearing is pretty low though. Could the tranny be slipping at all? Do you notice that it shifts into second and then third right away when you take off? Is it actually going into all three gears. Is it stuck in low lock? Just a few things to think about.

I don't want to hijack this thread, as I think others could benefit from this too. My truck shifts into second and then into third right away unless I baby it. I can't ever hear it shift into third unless I putt around like a grandma. Is this normal for a TH350?