Originally Posted by 81-F-150-Explorer

According to the 1981 F-150 Owners Manual.

Trailer Class I

tounge load 10 to 15% of trailer weight, 200LBS max.

Trailer weight, up to 2000LBS.

Cooling package, Extra Cooling.

towing package: LD

Trailer Hitch: Weight Carrying

GVWR MIN: 5020 / 5800 / 5450 / 6100

GCWR MAX: 7050 / 7600 / 7250 / 7900

Engine Required:

4.9L / 5.0L / 5.8L

min axle ratio 3.00

Automatic transmission required.

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Trailer Class II:

tounge load 10 to 15% of trailer weight.

Trailer weight, 2000 to 3500LBS.

Cooling package, Super Cooling.

towing package: HD

Trailer Hitch: Weight Distributing

Stabilizer bars: Front and rear

GVWR MIN: 5250 / 5800 / 5450 / 6100

GCWR MAX: 8225 / 8775 / 8425 / 9075

Engine required 4.9L / 5.0L / 5.8L

min axle ratio:
4.9L and 5.0L: 3.25
5.8L: 3.00 (3.25 Canada)

Automatic transmission required.

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Trailer Class III:

tounge load 10 to 15% of trailer weight.

Trailer weight, 3500 to 5000LBS.

Cooling package, Super Cooling.

towing package: HD

Trailer Hitch: Weight Distributing

Stabilizer bars: Front and rear

GVWR MIN: 5250 / 5800 / 5450 / 6100

GCWR MAX: 9500 / 9800 / 9700 / 9800

Engine Required:
5.8L

min axle ratio 3.00, 3.25 in canada.

Automatic transmission required.

You have to upgrade to a F-250 to tow more, according to the manual.


So according to the 1981 owners manual, it doesn't recomend you tow anything with this vehicle at all. (possibly due to clutch wear and warrantee) though in my personal experience, 2000LBS would be maximum without mods, IMO.