at 65mph I am running at 3000 rpm. Tis is a 6.4 with a five speed trans. It seems like it has no overdrive. Could this be true or is this normal. Ron

This sounds about right as most of my newer vehicles run about 2500-3k rpm at 65mph.

In an automatic, I would assume that 5th IS overdrive?

this is normal, there all like it

i own a 2008 f450 king ranch with the 488 gears at 65mph i run at just over 2 grand fer rpm

what gears are in it with a 373 gaer you should be for 1700 2000rpm did you push your override on its on the end of your gear shift

i would think that is too high... sounds like its either still in fourth or you have other issues... or one very tall gear in it...

is this a diesel? a diesel usually runs lower rpm's because thats where they generate the most power and are designed that way thus resulting in better fuel milage in a diesel, a gas job will usually run from 2500 to 3500 from 65 to 70 mph while the diesel may only be turning 1500 to 2200 rpms at the same speed

My 450 runs about the same Rpms and I took it to the dealer and they said 3k to 3500 is normal for a 6.4.