Ford F-150 Owner's Manual page 187

Towing a trailer places an additional load on your vehicle's engine,
transmission, axle, brakes, tires and suspension. Inspect these
components carefully periodically during, and after any towing operation.
Exceeding the maximum GCWR could result in extensive damage
to your vehicle and personal injury.
Do not exceed the GVWR or the GAWR specified on the
certification label.
Towing trailers beyond the maximum recommended gross trailer
weight exceeds the limit of the vehicle and could result in
engine damage, transmission damage, structural damage, loss of vehicle
control, vehicle rollover and personal injury.
Regular Cab 4x2 (126" wheelbase)
Engine Rear axle ratio
4.2L (with
manual
transmission)
4.2L (with
automatic
transmission)
4.6L
4.6L
5.4L
5.4L
2006 F-150 (f12)
Owners Guide (post-2002-fmt)
USA (fus)
Tires, Wheels and Loading
Maximum
GCWR-lb. (kg)
3.31 7200 (3266)
3.55 8500 (3856)
3.55 10000 (4536)
3.73 10500 (4763)
3.55 11500 (5216)
3.73 12000 (5443)
3.55 13000 (5897)
3.73 13500 (6123)
Maximum
trailer
weight-lb. (kg)
2400 (1089)
3700 (1678)
5200 (2358)
5700 (2585)
6600 (2993)
7100 (3220)
8000 (3628)
8500 (3855)
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