Darryl&Rita

But wouldn't a 550 be a mile long to carry a Jeep on deck? I looked at a 5500 Ram last time I was in the ***********, but something on the numbers didn't jibe. I don't remember what it was, exactly, but it looked a little light somewhere. It may have even been WB, I was just killing time while getting service done, so I wasn't looking to hard.
I have had a class 1 license w/air since 1988(as a condition of employment), but my gear experience ends at an ancient gas powered tandem grain truck. It was a 4 or 5 speed with a 2 speed rear, called "Old and Slow" I think it had syncro'd gears other than 1st, but it's been years.

RamPB331

It was a synchronized main, but I've spent a bit of time on an old IHC with a 5x4 in it. Engine is a complete dog 392 gasser, that Dad is afraid will eventually puke on us. As for HD transmissions, and hurrying up, it depends on the engine. Most engines are kinda slow on the decel, owing to lack of backpressure, so you can't hurry them up. A Detroit 6V92 is pretty quick on the decel. My ol' man's first semi tractor was an IH S2575 with a 6V92TA. Previous owner told him to shift it like he was mad at it. New tractor is a Pete with a Cat 3176E and a RR. Both were 9 speeds (1st is a Low Hole gear). Definitely a more refined experience with the Pete.

Sounds like the size of truck you'll be getting is properly classified as Medium Duty and would have a 7 or 8 speed at best in it. If you can, an Allison 2000 series would be good for an automatic. I drove a tri-axle late 60s IHC Fleetstar (IIRC) farm dump with a DT466 hooked to an Allison AT-540. Pretty darn good setup in a classic rig. The truck was rebuilt and the transmission I'm sure was not original equipment.

mulepackin

Just thought I'd throw two things that struck me the most when we bought a class 8 truck for our ranch operation. I am driving a 10 speed in our 95 IHC 9700 cabover. It is a progrssive shift, so you start at a lower RPM, and each subsequent shift requires a higher RPM and road speed. Conversely, coming down requires the same attention. Bit of a learning curve there. Also, after driving trucks with more gears, it's obvious more gears keeps you in your power range more often.