Ford F-250 Super Duty (1999 year). Manual — part 35

F-350 with automatic transmission

Engine

Rear axle

ratio

Maximum GCWR-kg

(lbs.)

Maximum trailer

weight-kg (lbs.)

1

5.4L

3.73

6 124 (13 500)

4 536 (10 000)

5.4L

4.10

6 804 (15 000)

4 536 (10 000)

6.8L

3.73

7 711 (17 000)

4 536 (10 000)

6.8L

4.30

9 072 (20 000)

4 536 (10 000)

1

Conventional/Class IV trailer hitch only. Fifth wheel trailer maximum

weights can be calculated by subtracting GVW from GCWR.

F-450 with manual transmission

Engine

Rear axle

ratio

Maximum GCWR-kg

(lbs.)

Maximum trailer

weight-kg (lbs.)

1

6.8L

4.88

9 979 (22 000)

4 536 (10 000)

6.8L

5.38

9 979 (22 000)

4 536 (10 000)

1

Conventional/Class IV trailer hitch only. Fifth wheel trailer maximum

weights can be calculated by subtracting GVW from GCWR.

F-450 with automatic transmission

Engine

Rear axle

ratio

Maximum GCWR-kg

(lbs.)

Maximum trailer

weight-kg (lbs.)

1

6.8L

4.88

10 886 (24 000)

4 536 (10 000)

6.8L

5.38

11 794 (26 000)

4 536 (10 000)

1

Conventional/Class IV trailer hitch only. Fifth wheel trailer maximum

weights can be calculated by subtracting GVW from GCWR.

F-550

Engine

Rear axle

ratio

Maximum GCWR-kg

(lbs.)

Maximum trailer

weight-kg (lbs.)

1

6.8L

4.88

10 886 (24 000)

4 536 (10 000)

6.8L

5.38

11 794 (26 000)

4 536 (10 000)

1

Conventional/Class IV trailer hitch only. Fifth wheel trailer maximum

weights can be calculated by subtracting GVW from GCWR.

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137

Preparing to tow

Use the proper equipment for towing a trailer, and make sure it is
properly attached to your vehicle. See your dealer or a reliable trailer
dealer if you require assistance.

Hitches

Do not use hitches that clamp onto the vehicle’s bumper or attach to the
axle. You must distribute the load in your trailer so that 10% of the total
weight of the trailer is on the tongue.

Load equalizing hitch

When hooking up a trailer using a load equalizing hitch, always use the
following procedure:

1. Park the unloaded vehicle on a level surface. With the ignition on and
all doors closed, allow the vehicle to stand for several minutes so that it
can level.

2. Measure the height of a reference point on the front and rear bumpers
at the center of the vehicle.

3. Attach the trailer to the vehicle and adjust the hitch equalizers so that
the front bumper height is within 0–13 mm (1/2 inch) of the reference
point. After proper adjustment, the rear bumper should be no higher
than in Step 3.

Adjusting an equalizing hitch so the rear bumper of the vehicle
is lower or higher than it was unloaded will defeat the function

of the load equalizing hitch and may cause unpredictable handling.

Safety chains

Always connect the trailer’s safety chains to the vehicle. To connect the
trailer’s safety chains, cross the chains under the trailer tongue and allow
slack for turning corners.

If you use a rental trailer, follow the instructions that the rental agency
gives to you.

Do not attach safety chains to the bumper.

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138

Trailer brakes

Electric brakes and manual, automatic or surge-type brakes are safe if
installed properly and adjusted to the manufacturer’s specifications. The
trailer brakes must meet local and Federal regulations.

Do not connect a trailer’s hydraulic brake system directly to your
vehicle’s brake system. Your vehicle may not have enough

braking power and your chances of having a collision greatly increase.

The braking system of the tow vehicle is rated for operation at the
GVWR not GCWR.

Trailer lamps

Trailer lamps are required on most towed vehicles. Make sure your
trailer lamps conform to local and Federal regulations. See your dealer or
trailer rental agency for proper instructions and equipment for hooking
up trailer lamps.

Using a step bumper

The rear bumper is equipped with an integral hitch and requires only a
ball with a 25.4 mm (one inch) shank diameter. The bumper has a 2 270
kg (5 000 lb.) trailer weight and 227 kg (500 lb.) tongue weight
capability.

If it is necessary to relocate the trailer hitch ball position, a
frame-mounted trailer hitch must be installed.

Driving while you tow

Do not drive faster than 88 km/h (55 mph) when towing a trailer.

Speed control may shut off if you are towing on long, steep grades.

When towing a trailer:
• Use a lower gear when towing up or down steep hills. This will

eliminate excessive downshifting and upshifting for optimum fuel
economy and transmission cooling.

• Anticipate stops and brake gradually.
Exceeding the GCWR rating may cause internal transmission
damage and void your warranty coverage.

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139

Servicing after towing

If you tow a trailer for long distances, your vehicle will require more
frequent service intervals. Refer to your Scheduled Maintenance guide
for more information.

Trailer towing tips
• Practice turning, stopping and backing up in an area before starting on

a trip to get the feel of the vehicle trailer combination. When turning,
make wider turns so the trailer wheels will clear curbs and other
obstacles.

• Allow more distance for stopping with a trailer attached.
• The trailer tongue weight should be 10–15% of the loaded trailer

weight.

• After you have traveled 80 km (50 miles), thoroughly check your

hitch, electrical connections and trailer wheel lug nuts.

• When stopped in traffic for long periods of time in hot weather, place

the gearshift in P (Park) (automatic transmissions) or N (Neutral)
(manual transmissions). This aids engine cooling and air conditioner
efficiency.

• Vehicles with trailers should not be parked on a grade. If you must

park on a grade, place wheel chocks under the trailer’s wheels.

Launching or retrieving a boat

When backing down a ramp during boat launching or retrieval,
• Do not allow the static water level to rise above the bottom edge of

the rear bumper and

• Do not allow waves to break higher than 15 cm (six inches) above the

bottom edge of the rear bumper.

Exceeding these limits may allow water to enter critical vehicle
components, adversely affecting driveability, emissions and reliability.

Replace front and rear axle lubricants anytime the axles have been
submerged in water. Axle lubricant quantities are not to be checked
unless a leak is suspected.

Recreational towing

If you may want to tow your vehicle behind another vehicle, such as an
RV, follow these guidelines:

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