Where I worked, we had all 4 tires filled on a new Montana back in '08 or so. The vendor we used in Harrisburg PA had choices in different weights and densities. He guided us based on information we provided. The tractor had a very stiff ride, much like the R4's were inflated to the max. Bright side was even the worst of our people couldn't hurt them. I can't say if the tires developed flat spots because we didn't run it on nice smooth surfaces.
The first foam-filled tires I remember seeing were on a telehandler we were using on a project back around 1990. This machine ran over all sorts of construction debris, rebar, stakes etc. One of the tires had a chunk missing that was about 1/2 on the tread and 1/2 on the sidewall. No part of the tire remained in that roughly 6-8" diameter area and the foam fill was sticking out a bit past flush there. It looked like there was a foam pillow trying to escape. Of course the foam was many times more dense than pillow foam.
The first foam-filled tires I remember seeing were on a telehandler we were using on a project back around 1990. This machine ran over all sorts of construction debris, rebar, stakes etc. One of the tires had a chunk missing that was about 1/2 on the tread and 1/2 on the sidewall. No part of the tire remained in that roughly 6-8" diameter area and the foam fill was sticking out a bit past flush there. It looked like there was a foam pillow trying to escape. Of course the foam was many times more dense than pillow foam.
