2015 FORD F750 flat tire

Checking Tire Pressure
Always check inflation pressure when tires are cold. Never bleed air from
hot tires to relieve normal pressure build-up. Normal increase in pressure
due to service conditions is 10–15 psi (69–103 kPa), which is allowable
in truck tires.
Tires should be properly inflated to manufacturers’ recommended
pressure for the size and service load in which the vehicle is being used.
See the specific tire manufacturer with which your vehicle is equipped
with for the latest information concerning service load and inflation
pressure.
It is particularly important to keep moisture from the inside of tires, and
proper selection of air compressor equipment, proper air line routing,
and the use of shop air dryers is strongly recommended to avoid
moisture in the high pressure air used for tire inflation.
Under-inflation
Do not allow tires to become under-inflated; increased flexing due to
under-inflation causes heat build-up within the tire components. This
leads to reduced strength, breakdown of the rubber compounds, and
possible separation of the tire components (such as ply and tread
separation and reduced retreadability).
Under-inflation is the primary cause of premature tire concerns including
sudden loss of air. In addition, low inflation causes an increase in rolling
resistance. This results in reduced fuel mileage, a loss in tread mileage,
and uneven wear due to increased tread movement. To determine proper
inflation, see the tire manufacturer load and inflation guide, which you
can find on the tire manufacturer website or at your local truck tire
dealer.
Tire Inspection
Check the tires for abnormal wear patterns and proper inflation
pressures. Repair or replace cut or broken tire casings.
Inspect tires for the following conditions. If any are present, remove and
repair, retread, or scrap the tire as the condition dictates.
•Any blister, bump or raised portion anywhere on the surface of the
tire tread or sidewall (other than a bump made by a repair). These
indicate the start of internal separation.
•Any cut that reaches to the belt or ply cords, or any cut that is large
enough to grow in size and depth.
•Any nail or puncturing object.
•If a tread groove is holding a stone or object that is starting to drill
into the tread base, remove the object.
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Proper tire inflation, toe-in adjustment, loads, and road speeds are
important factors governing tire mileage, steering ease and
maneuverability.
Tire Loading
WARNING:Loading tires beyond their rated capacity decreases
tire life requiring more frequent replacement of tires. Overloading
creates an unsafe condition that may result in sudden air loss from a
tire failure resulting in an accident that could cause property damage,
personal injury or death.
Note:Your GAW/GVW rating is correct at the time of your vehicle
production, and reflects the exact rating of the tires specified. When
replacing tires, make sure that the replacement tire load rating (listed in
pounds and kilograms on the tire sidewall) is the same or higher than
the tire that you are replacing. Failure to do so adversely affects
maximum load carrying capacity. Tires with the same size specification
do not always have the same load specification.
Note:The tire installed as original equipment may not be the same as
the tire specified on the DOT label, but has enough load capacity to
carry the GAW/GVW specified.
Note:Tires with the same size specification do not always have the same
load specification.
Matching Tires
Dual Tires:Dual tires should be matched using tires of equivalent size.
Do not mount tires that differ more than one-quarter inch (6
millimeters) in diameter or three-quarters inch (19 millimeters) in
circumference on the same dual wheel assembly.
Mixing:Never mix bias and radial tires on this vehicle. Never mix
different tire sizes or constructions on the same axle.
Rotation:
Rotation is always advisable:
•If there is irregular wear on the front (steering) axle tires, move to
rear position.
•In a dual assembly, reverse the position of the tires if one tire wears
much faster than its mate does.
•On the drive axle, if heel and toe wear or alternate lug wear occurs,
rotating the tires from one end of the axle to the other end of the
axle may help even out this wear.
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Rotation may not advisable:
•Front (Steering) Axle:Remove tires when tread wears down to
four–thirty seconds inch (3 millimeters) or less. Retread or rotate
worn tires to drive position. We do not recommend using retreaded
tires on steering axles.
•Rear Axles:Remove tires when tread wears down to two–thirty
seconds inch (2 millimeters).
If using a rib tire on front axle and lug or off-road type on rear axle
positions:
•Front (Steering) Axle:Replace tires at front wheels when tread is
worn to four–thirty seconds inch (3 millimeters) or less.
•Rear Axles:Remove tires when the tread wears down to two–thirty
seconds inch (2 millimeters) or less. Tires identified with the word
re-groovable molded on the sidewall can be re-grooved. There must
be a minimum of three–thirty seconds inch (2.5 millimeters) of
under-tread at the bottom of the grooves.
Wheel and Tire Balancing
Out-of-round or out-of-balance wheels or tires can cause vehicle
vibration, bounce and shimmy. Replace damaged or out-of-round wheels.
You can correct out-of-round tires and wheel assemblies by re-clocking
the tire relative to the wheel.
You should then dynamically balance the tire and wheel assembly.
Tire Wear
Radial tires can exhibit three types of normal wear patterns:
•Even
•Erosion
•Chamfer
Even wear:A sign that the tire is being properly used and maintained.
Erosion wear:Also called rolling wear, channel or river wear, erosion
wear occurs more often on free-rolling tires. This is an indication of
using the tire in a slow wearing operation. What happens is that the belt
plies are held very rigid and the tread is not allowed to distort as it
passes through the contact area. Wear only occurs at the edge of the
tread. No corrective action required. If erosion gets to be one–sixteenth
inch (2 millimeters) or more, you can rotate the tire to a drive axle.
Chamfer or shoulder wear:With tires inflated properly, this is a
normal tendency of most radial tire designs. If both inside and outside
shoulders are wearing evenly around the tire, no further action is
required. Over-inflation is not effective in correcting this effect.
248Wheels and Tires
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Irregular Wear:If irregular wear is present, check the axle alignment,
tire pressure, wheel balancing, shock and suspension component
condition, and wheel bearing end play.
This condition not only shortens tire life, but also adversely affects the
handling of your vehicle, which is dangerous.
Rotating tires from one wheel position to another is an often-used way to
even out many types of irregular wear or to avoid it altogether. Some of
the more effective tire rotation programs are:
•You can rotate steer tires that have developed some type of irregular
wear pattern to drive axles if using rib tires on all wheel positions.
Applying steer tires to a drive position often cleans them. You can
move them back to the steer axles or run out to re-tread stage on the
rear axle.
•Another rotation possibility for fleets with rib tires in all wheel
positions is to break in the new steer tires in the drive axle positions,
then move them to steer axles. This wears away tread rubber
relatively quickly in the early life of a tire when it is most likely to
develop an unusual wear pattern.
•You can place drive axle tires on the other end of the same axle to
reverse the direction of rotation. This is often helpful if a heel and
toe or alternate lug wear pattern has developed.
You can help minimize irregular wear by:
•Using the right inflation pressure for the load being carried.
•Maintaining proper front wheel alignment, especially toe-in, to
specifications.
•Maintaining proper tire and wheel balance.
•Maintaining shock absorbers and suspension components.
Use of Tire Chains
See the chain manufacturer’s recommendation for correct tire chain
usage, installation and removal.
WHEELS
General Information
Note:Remember to replace the wheel air valves when replacing the road
tires at the end of their useful lives.
Inspect, lubricate and adjust wheel bearings at regular intervals. This is
especially important if operating in deep sand, mud or water. See the
Capacities and Specificationschapter.
Mount wheel balance weights on the dome-side of the wheel only. Failure
to do so may result in loss of wheel weight or damage to brakes or
wheels.
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Owners Guide gf(ownloose), 1st Printing, December 2013
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Note:Make sure the tire valve stem clears the brake caliper when
installing the tire and rim assembly on disc-brake equipped axles. The
use of a tire manufacturer’s stem forming tool is the only acceptable
method of obtaining clearance when necessary.
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 or mounting hardware.
Changing Wheel Types
WARNING: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.
Consult your dealer or wheel or rim distributor before attempting any
wheel or fastener changes.
TECHNICAL SPECIFICATIONS
Wheel Lug Nut Torque Specifications
Note:Do not use lubrication on dry threads. Where excessive corrosion
exists, you can apply a light coat of lubricant on the first three threads
of the stud bolt. Keep lubricant away from the:
•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.
Size Nut MountingTorque
ft-lb N•m
22 mm Flange 450–500 610–678
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)