I've got a simple problem for y'all but it its going to have a
complicated answer. Let me set up a senario: You've got a
rope,cable,chain, or other pulling device that (ignoring shock
loading) has a break strength of 40,000 lbs. How large of a vehicle
can I "get unstuck"? Specifically though I'd like to know how much
force to pull a fully loaded tractor-trailer (semi) full of beets out
of mud (up to its axle).

I realize that this depends on the how the vehicle is stuck, what it
is stuck in, how deep, whether or not the vehicles wheels are able to
role, etc...
A better question might be:

How much pulling force, without "jerking" or "getting a run at it",
can a vehicle produce under ideal circumstances.
4X4 Pickup Truck?
Semi?
2WD Tractor?
4WD Tractor?
Dozer?

Tractor manufacturers sometimes give a PTO HP or even a draw-bar HP
but I can't get a draw-bar pulling force from HP (without a few more
details). Taking engine torque and multiplying it by the drive ratio
seems like perhaps the only way to get somewhat close (although
perhaps a bit exaggerated).


Josh