IDIBRONCO
IDIBRONCO
I got to borrow a buddy's F250 4x4 with IDI/ZF5/3.54 for almost a year. It's was a great truck for basic transportation and moderate chores.
I completely agree with both of these.Both my 6.9 and 7.3 are zf5s with 3.55s gears. Great combination imo.
Rock
These engines can be run against the governor for hours at a time so don't worry too much about high RPM. The fuel mileage will suffer from doing that, but the engine won't be hurt. Unless your cooling system isn't up to par and the sustained high RPM causes it to overheat. I think that your cooling system would have to be in pretty bad shape or maybe the fan clutch would need to be replaced if it got hot while running empty at any RPM.I'm more concerned with noise and RPMs
As far as the noise goes, one down side to the IDI engine is that it's noisy. That's why I have a loud (to me anyway) radio in my truck.