Trucks, Freightliner, Volvo, Kenworth, etc, normally have air system
set @120psi or so.

I've found the highest I can inflate the tires using the truck
air system & a 50' hose is 97-98psi.

Need a bit more. Looking for 115psi on the steers(cold) & 105psi on
the drives.

Was wondering if an air powered booster pump would be possible?

Say, 50% of the airstream as high-pressure supply, and the rest to
drive the booster?

If not practical, any easier/better way?

thanks

gary