Volvo FM Handbook page 648

Towing backwards
Tow from the rear axle, rear spring anchorage or
trailer hitch hook.
If something happens 637
The towing brace may only be
used when towing on good roads.
It is not intended for recovery.
Note!
Lock the towing pin by turning the
handle 60° clockwise. Each towing
brace may be loaded from straight
ahead with half the gross weight of
the truck.
Warning!
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