we did go up one of the 2, either E48 or E29. Probably 48. Forgot what trucks were there but I think there may even have been a full size pickup, not sure. I was in Brent's 80. It did not have any serious trouble. There were one or 2 steep loose rock tight turns spots on the way up that I remember but nothing too bad. So a fairly big capable vehicle could make it. A 40 should have had no trouble. I think I do remember the pickup struggling with traction and tight spots, though. May even have had to be strapped once and had a flat. But was not a problem for a normal mildly-built 80. Could have changed since then (3 or 4 years ago), of course. There was a nice lookout spot up top (Sherman Peak?). The initial climb was through a bleak burned spot and was not particularly pretty, but it got greener later. It was a long day but we were coming from and going back to Monache. I think you should plan for a good half day on dirt but we took the long way out.