FORD 2003 F-550 v.1 - Manual (Page 123)

Never drive with chains on the front tires of 4WD vehicles without also
putting them on the rear tires. This could cause the rear to slide and
swing around during braking.
Tires, Replacement Requirements
Do not use a size and type of tire and wheel other than that
originallyprovided byFord Motor Companybecause it can affect
the safetyand performance of your vehicle, which could result in an
increased risk of loss of vehicle control, vehicle rollover, and/or serious
personal injuryor death.
Make sure all tires and wheels on the vehicle are of the same size, type,
tread design, brand and load-carrying capacity. If you have questions
regarding tire replacement, see an authorized Ford or Lincoln/Mercury
dealer.
If you nevertheless decide to equip your 4WD for off-road use with tires
larger than what Ford Motor Companyrecommends, you should not use
these tires for highwaydriving.
If you use anytire/wheel combination not recommended byFord Motor
Company, it may adversely affect vehicle handling and could cause
steering, suspension, axle or transfer case failure.
Do not use “aftermarket lift kits” or other suspension modifications,
whether or not theyare used with larger tires and wheels.
These “aftermarket lift kits” could adverselyaffect the vehicle’s handling
characteristics, which could lead to loss of vehicle control or rollover and
serious injury.
Tires can be damaged during off-road use. For your safety, tires that are
damaged should not be used for highwaydriving because theyare more
likelyto blow out or fail.
You should carefullyobserve the recommended tire inflation pressure
found on the safetycompliance certification label attached to the left
front door lock facing or door latch post pillar. Failure to follow tire
pressure recommendations can adverselyaffect the wayyour vehicle
handles. Do not exceed the Ford Motor Companyrecommended pressure
even if it is less than the maximum pressure allowed for the tire.
Driving
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