"Allen" wrote in message
. ..
I had a John Deere 318 with hydrostatic drive. Built a frame with hitch
on
the front of the tractor, much better for pushing the airplane into the
hangar. Was using it on a P-Baron, had to fill the tires with calcium
fluid
to have enough traction to get it up the little incline into the hangar.

What does the fluid in the tires do?