Another thing has been on my mind:

Juliet is stronger than a jeep in full throttle? She should have been sucked down that hole faster than you can say "adios".

Ok, the chain's iron content may be different than the jeep? Yet, I'll bet a '70's jeep had mucho steel - vis-a-vis IRON.

A steel chain and Juliet's strength is proportionate to a jeep and it's horsepower?

I don't think so...unless Juliet has been hitting the gym between episodes.