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Normal maintenance
Over a period of time, if not routinely cleaned, a slight film of oil can
collect dirt around the rubber fill plug and face, which could appear to
be a leak. Routine cleaning ensures that the lube level can be easily
observed through the clear window as intended. In situations where the
window is clean on the outside but discolored on the inside, the lube
level may be checked by inserting a finger through the rubber check
vent hole.
The specified lube level for a clear window type hubcaps is from the
minimum line to + 5/16 inch above the minimum line.
If the lube level should suddenly drop dramatically below the minimum
level, see the Service Manual for diagnostic procedure.
Installation, tightening and alignment
8–lug wheel
10–lug wheel
When installing wheels, be certain that the threads on studs and nuts are
clean to permit correct torquing of nuts. The mounting surfaces of rims,
wheels, spacer rings and clamps must be free of dirt, rust, lubricants or
damage.
Use a wire brush to clean the mounting contact surfaces. Do not use
lubricant on threads.
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USA(fus)
Maintenance and Specifications
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After the rim or wheel has been properly tightened, it should be checked
for alignment. Rotate the wheel with a piece of chalk attached to a
steady, firm surface, and placed to just barely clear the outside surface of
the tire bead seat. This procedure will point out the high spot. A high
spot does not necessarily mean that the lug nuts have been unevenly
tightened. This condition or misalignment could be caused by a bent
wheel.
Checking the alignment of the wheel/rim installation is more important
on cast spoke rims since the rims can be drawn out of alignment when
improperly tightened. Use the following installation procedures.
Disc wheel with flange nuts (hub-piloted)
Front wheel mounting of flange nut
system
1. Flange nut
2. Wheel(s)
3. Brake drum
4. Wheel stud (22 mm)
5. Wheel hub
Rear wheel mounting of flange nut
system
1. Flange nut
2. Wheel(s)
3. Brake drum
4. Wheel stud (22 mm)
5. Wheel hub
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Supplement
USA(fus)
Maintenance and Specifications
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1. Slide inner rear or front tire and wheel in position over studs and push
it back as far as possible. Use care so that the threads on studs are not
damaged.
2. Position the outer rear tire and wheel in place over the studs and
push it back as far as possible. Use care so that the threads on studs are
not damaged.
3. Run the nuts on the studs until they contact the wheel(s). Rotate the
wheel assembly a half-turn to permit the parts to seat.
4. Draw up the nuts alternately following the crisscross sequence
illustrated underInstallation, tightening and alignment. Do not fully
tighten the nuts. This will allow uniform seating of the nuts and ensure
even face-to-face contact of the wheel and hub.
5. Continue tightening the nuts to the torque specifications in the torque
chart using the same crisscross sequence shown.
6. After operating the vehicle approximately 50 miles (80 km), check the
nuts for tightness. Some natural seating of parts may be encountered
and the torque on the nuts will drop. Retighten all nuts to specifications.
Once a week, inspect and retighten the wheel stud nuts.
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Supplement
USA(fus)
Maintenance and Specifications
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Aluminum rear disc wheel with flange nuts (hub-piloted)
1. Flange nut
2. Wheel(s)
3. Brake drum
4. Wheel stud (22 mm)
5. Wheel hub
6. Wheel locator pad
Prior to re-installing rear aluminum hub-piloted wheels, clean each wheel
locator pad on the hub from all dirt, rust and foreign material. Apply a
light coat of chassis grease, never-seize or disc brake corrosion control
grease, only to the wheel locator pad.
When installing the tire and rim assembly on disc-brake equipped axles,
make sure the tire valve stem clears the brake caliper. The use of a tire
manufacturer’s stem forming tool is the only acceptable method of
obtaining clearance when necessary.
Note:Always observe the following instructions:
Failure to follow these instructions could result in property
damage, personal injury or death
1
6
5
4
32
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Supplement
USA(fus)
Maintenance and Specifications
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•Always loosen rim clamps before complete removal of nut from stud
(cast spoke wheels). With loosened nuts on stud, strike clamps with a
heavy hammer and be sure each clamp is loose.
•Always deflate tires completely before removing locks or side rings.
•Always inflate tires in a safety cage.
•Never mix rim side rings or lock rings of different types,
manufacturers or sizes.
•Never use cracked, bent or badly rusted parts.
•Never re-inflate flat tires on-vehicle; use the spare tire.
•Never add air until each side ring or lock ring is fully seated.
•Never hammer side ring or lock ring on a partially- or fully-inflated
tire.
Proper torque
It is important to tighten and maintain wheel and rim mounting nuts to
the proper torque. Loose nuts or over-tightened nuts can lead to
premature wear and possible failure of the wheel and/or mounting
hardware.
Changing wheel types
Consult your dealer or wheel/rim distributor before attempting any wheel
or fastener changes.
Use only the same type and style wheels and mounting hardware
to replace original parts. Failure to do so may result in an
assembly that looks fine, but does not fit together properly. This could
possibly cause wheel or fastener failures which could result in property
damage, personal injury or death.
Note:Do not attempt to mix stud-piloted wheels or fasteners with
hub-piloted wheels or fasteners.
Note:Do not change from aluminum wheels to steel wheels or
vice-versa without changing the mounting hardware required or, with
flange-nut mounting systems, changing the hub and stud assembly.
2006 F-650/750(f67)
Supplement
USA(fus)
Maintenance and Specifications
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WHEEL NUT TORQUE
Size Nut mountingTorque
Ft. lb. N•m
22 mm Flange 450–500 610–678
Note:Do not use lubrication on dry threads. Where excessive corrosion
exists, a light coat of lubricant on the first three threads of the stud bolt
is permitted. Keep lubricant away from:
•Hex nut and rim clamp contact surfaces.
•Cap nut ball face and ball seat on the disc wheel.
•Flange nut washer surface and flat on the disc wheel.
TIRE/WHEEL RIM SELECTION AND INFLATION PRESSURES
Tire sizeLoad
rangeApproved
rim widthsAxle capacity
Front - lb.
(kg)/psi
(kPa)Rear - lb.
(kg)/psi
(kPa)
225/70R19.5 F 6.00, 6.757280 (3302) /
95 (655)13660 (6196) /
95 (655)
245/70R19.5 F 6.75, 7.508160 (3701) /
85 (586)15440 (7003) /
85 (586)
245/70R19.5 G 6.75, 7.509090 (4123) /
100 (690)17640 (8001) /
100 (690)
265/70R19.5 G6.7510000 (4536) /
115 (793)19440 (8817) /
115 (793)
7.50, 8.2510710 (4858) /
120 (827)20280 (9199) /
120 (827)
9R22.5 F 6.75, 7.509080 (4118) /
105 (724)17200 (7801) /
105 (724)
10R22.5 F6.7510000 (4536) /
100 (690)19760 (8963) /
100 (690)
7.5010410 (4722) /
100 (690)19760 (8963) /
100 (690)
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USA(fus)
Maintenance and Specifications
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Tire sizeLoad
rangeApproved
rim widthsAxle capacity
Front - lb.
(kg)/psi
(kPa)Rear - lb.
(kg)/psi
(kPa)
10R22.5 G6.7510000 (4536) /
115 (793)20000 (9072) /
115 (793)
7.5011350 (5148) /
115 (793)21420 (9716) /
115 (793)
11R22.5 G 7.50, 8.2512350 (5602) /
105 (724)23000 (10432)
/ 105 (724)
11R22.5 H 7.50, 8.2513220 (5996) /
120 (827)23800 (10795)
/ 110 (758)
12R22.5 H8.2514400 (6531) /
120 (827)27120 (12301)
/ 120 (827)
9.0014780 (6704) /
120 (827)27120 (12301)
/ 120 (827)
245/75R22.5 G 6.75, 7.509350 (4241) /
110 (758)17640 (8001) /
110 (758)
255/70R22.5 H6.7510000 (4536) /
115 (793)19660 (8917) /
115 (793)
7.50, 8.2511020 (4998) /
120 (827)20280 (9199) /
120 (827)
265/75R22.5 G 7.50, 8.2510410 (4722) /
110 (758)19220 (8718) /
100 (690)
275/70R22.5 H7.5013220 (5996) /
120 (827)24800 (11249)
/ 120 (827)
8.2513460 (6105) /
120 (827)24800 (11249)
/ 120 (827)
275/80R22.5 G 7.50, 8.2512350 (5602) /
110 (758)22700 (10296)
/ 110 (758)
295/75R22.5 G 8.25, 9.0012350 (5602) /
110 (758)23900 (10841)
/ 100 (690)
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USA(fus)
Maintenance and Specifications
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Tire sizeLoad
rangeApproved
rim widthsAxle capacity
Front - lb.
(kg)/psi
(kPa)Rear - lb.
(kg)/psi
(kPa)
295/80R22.5 H8.2514400 (6531) /
120 (827)27760 (12591)
/ 120 (827)
9.0014780 (6704) /
120 (827)27760 (12591)
/ 120 (827)
Tire inflation information
All tires with Steel Carcass Plies (if equipped):
This type of tire utilizes steel cords in the sidewalls. As such, they
cannot be treated like normal light truck tires. Tire service, including
adjusting the air pressure, must be performed by personnel trained,
supervised and equipped according to Federal Occupational Safety and
Health Administration (OSHA) regulations. For example, during any
procedure involving tire inflation, the technician or individual must
utilize a remote inflation device, and ensure that all persons are clear of
the trajectory area.
WARNINGAn inflated tire and rim can be very dangerous if
improperly used, serviced or maintained. To avoid serious injury,
never attempt to re-inflate a tire which has been run flat or seriously
under-inflated without first removing the tire from the wheel assembly
for inspection. Do not attempt to add air to tires or replace tires or
wheels without first taking precautions to protect persons and
property.
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Supplement
USA(fus)
Maintenance and Specifications
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