FORD 1999 F-550 v.1 - Manual (Page 174)

WRECKER TOWING
If you need to have your vehicle towed, contact a professional towing
service or, if you are a member, your roadside assistance center.
On 4x2 vehicles, it is acceptable to tow the vehicle with the front wheels
on the ground and the rear wheels off the ground using a wheel lift or a
slingbelt with T-hooks.
On 4x4 vehicles, it is recommended that your vehicle be towed with a
wheel lift or flatbed equipment with all the wheels off the ground.
However, a slingbelt with T-hooks and a wheel dolly can also be used.
A towing manual is available from Ford Motor Company for all authorized
tow truck operators. Have your tow truck driver refer to this manual for
proper hook-up and towing procedures for your vehicle.
Roadside emergencies
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