Is the rope on his jeep a metallic cable or a non-metallic (synthetic or natural fiber) rope? The reason I ask is that there is commercially available whipping twine (FSE Robline) and "dipped" rope whipping (Star Brite dip-it) used by sailors on the latter.

From personal experience, I would recommend staying away from Nylon (too stretchy) and Polypropylene (too slippery) whipping twines, and if possible, use a sailmakers whipping. Whipping twine diameter should be approximately 1/16 (1/12-1/24) the diameter of the rope, but smaller will work in a pinch.
_________________________
Hope for the best and prepare for the worst.

The object in life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane