Transfer and front axle switches?

Yes.

[Xfer...] HIGH, [Axle] OFF

You only need the front axle engaged when you want four-wheel-drive.

 

Front axle switch engages front axle.
Xfer switch changes from high gear to low gear for offroad situations. Stays in HI for normal driving.
I'd like to see a picture of the truck. It sounds really cool.

 

Low range is for offroad situations. Even in overdrive at 2000 rpm in low range top speed would be like 15 MPH

 

OH.

A 4x4 like a Jeep?

DOH **** BANGS HEAD. Im so stupid, here I am thinking a proper TRACTOR TRAILER... *Weeps in my own stupidty.

 

Buttons taking place of shifters in the floor....

 

I have a 2005 International 7300 4x4 Bucket Truck and I am experiencing a similar problem. When the weather is freezing or below, the transfer case will not engage either high or low gear. I can put the truck in gear and when I release the clutch the truck wont move forward or reverse but the drive shaft turns freely. I also have the high and low switch and can hear a continuous flow of air from underneath the truck.

 

Sounds like ice in the lines.

 

Did you ever figure olthis out we have a similar problem... Truck moves after playing with the switches but is stuck in low gear.