Stu has it right... the reason you must tie down the car by it's "unsprung"
components (wheels, control arms, axles) is because there would be
over-loading (possibly extreme) on the tie downs whenever you go over bumps
or swooping dips. When the car's springs compress during the bump/dip, there
will some amount of slack in the tie downs, that is then suddenly "jerked"
tight during rebound. At some point, a tie down breaks, allowing slack in
the remaining tie downs which then break and it's anyone's guess where the
car ends up. It won't be pretty.
This is also why you want to really snug the car down so as to minimize the
"available compression" of the tire sidewalls going over the same bumps.
This is true no matter the relative weight of the car and trailer. The only
exception I know of is if you tie down the car to where the springs will no
longer compress over bumps.
Stephen Waybright
>From: stubrennan@attbi.com
>Subject: Re: Tying the Tiger
>If you secure your car by pulling down on the body, not the diff or front
>wheels, then what happens when you hit a really big bump? The tie downs go
>slack for a moment, then when the body comes back up there's a sudden
impulse
>of force. I'll bet you could break stuff that way.
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