Looking at a 2008 f450 lariat, 95,000miles
It has the 4:30 gears, what rpms are you guys seeing at highway speeds, specificly between 70-80 mph.

What is the normal operating rpm range of the 6.4

I currently have a 05 ram 3500 dually on 35s and at 70mph im turning 1800. And at 80 just barly over 2k.

Getting rid of the cummins, 4 trans in one year, the last 2 with in last month alone.

I realize with 4:30 gears and stock tires she will run high rpms on highway and im ok with that but if the tales iv heard are true that at 80 she sits at 3k rpm then that will detur me from buying.

 

I have a 6.4l f350 2008 with 4.30 gears. I run at 2k rpm at 60mph. If i push it to 75-80 i get close to 3k rpms. As far as i know the f450 is a bit heavier due to the oversized axle.