I know the trail was originally a Model-T and jeep road, but it is long overgrown and the area was made wilderness in 1986 (?) so the wreck must be old. What surprises me is how the paint still looks fairly fresh. I didn't hike down to it (I had a full pack and was fairly beat), but one of you must have looked at it up close.
I've seen the vehicle but don't know the whole story. However the Weatherford trail did used to be open to vehicles long ago (I think the road was built back in 1924 or thereabouts), so we know how it got there.
lcarreau's link shows a piece of the truck has a manufacture date of 1959, well after the actual road company failed; it could have been any time after that and before the wilderness. I don't know how long the road remained "drivable." I'm still surprised that the paint is in decent shape, I believe all the chrome and anything strippable is gone.
It may have been flipped, but the picture doesn't capture the steepness of the slope - it's possible that it rolled down and came to rest on its side against the tree.