gear ratio and axle specs

The 23K axle with the 20K suspension would be fine. You won't be running more than 20K legally anyway, and air bags are MUCH cheaper than axle housings if you do happen to exceed the rating by a bit. It would also be an easier way to get a stout axle and keep the lower GVWR you're looking for.

The driver controlled locking diff will come in handy if you find yourself in a situation where 1 drive tire just doesn't have enough traction to move the truck. Without it, the drive tire with the least traction will get all of the power just as soon as it breaks loose while the other tire just sits there looking pretty. Lock in and BOTH drive tires will spin.

Now if the dealer is calculating 78 mph with that gearing, is that your top speed as in it won't go any faster? Or is that where they say is a good cruising speed based upon where the engine runs most efficiently in the power band? I'm guessing that's a max speed...which you won't want to be running the engine as fast as it'll turn all of the time. Better off with a gearing that puts you into the engine's optimal operating range.

 

These are our 2 intown trucks, the one on the right is an FL112-has the 12,000 front axle and 21,000 rear. Started life as a single axle day cab and had it stretched to a 256 inch wb, then installed our box on the back.
Truck has a C10 with 305hp and 1200lb ft, Allison 6spd. 5.29ratio
We only haul furniture with it, and it just flat out gets it! If you are hauling produce, you might want to step up to the ISC motor for the extra torque.
This truck will cruise down the hiway at 75mph and 2000rpm, averages between 8-10 mpg.
It's at 2000 with 325,000 miles and have not had a lick of trouble from the motor or tranny. Build quality of the cab, well that's another story.

 

The International I have has the DT466. That is the 5 Int'l I've had and they have all been good motors.

Have you looked into the DT530?

 

Are dual leveling valves available as a factory option? All the loggers around here would spec their Kenworth air ride trucks with a leveling valve per side and it seems to make a world of difference when it came to sway or roll in turns.

 

Fredrd
Did you order truck and how did you have it specd?
Do you have truck on road and how is it going so far?
Thanks Leroy