Gulf Stream Indiana, Owner'S Manual

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15
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225 indicates the “contact patch” width. The contact patch is the amount of tire surface that actually comes into
contact with the pavement. In this case the width is 225 millimeters wide.
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75 indicates the height to width ratio of the tire.
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R identifies the construction type of the tire. R – Radial, B – Bias belted, D – Diagonal Bias.
Some tires may have a speed designation label in front of the construction type. Example – MR tires are rated for
use up to 81 mph. SR tires up to 112 mph. ZR tires carry the highest speed rating, and are safe for speeds over
150 mph. However, ZR tires should never be installed on any motor home or travel trailer. If no speed rating is
listed on the sidewall, the maximum speed for light truck tires is 87 mph, and for passenger cars 105 mph.
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16 is the rim size. This is the only measurement made in inches.
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E is the load range.
TIRE LOAD RATINGS
Load ratings for tires go up as the corresponding letter changes. For example, load range “E” tires have a heavier
rating than load range “D” tires. Load capabilities of tires change as the psi (air pressure) is lowered. As much as 220
lbs. of load carrying capacity is lost per tire for each 5 psi below the recommended inflation. This decreased load
amount varies from one tire manufacturer to the next, therefore it is recommended that you contact your tire
manufacturer for further information in this regard.
TIRE AIR PRESSURE
WARNING: PROPER TIRE AIR PRESSURE IS CRITICAL FOR SAFE OPERATION OF THIS VEHICLE! IT IS
REQUIRED THAT THE TIRE AIR PRESSURE IS CHECKED PRIOR TO EACH USE OF THIS VEHICLE.
When checking air pressures, if the tire has been driven more than 6 miles, you can add 4 to 6 psi to the rated
maximum “cold” inflation recommendations. For example, if the tire has a maximum rating of 90 psi cold, you can
inflate the tire to 96 psi after being driven on. Under inflation generates excessive heat (a tire’s worst enemy!),
increases tread wear in the shoulder area, and reduces your vehicle’s fuel economy.
Never mix radial, bias belted or bias type tires. Never mix brands. This can adversely affect vehicle handling and
stability. Use only the tire size that is listed on the Safety Compliance Certification Label. If you have a question about
the label, please call Gulf Stream.
The tire inflation tables provided by Goodyear and Michelen are shown at the end of this manual and are for general
purposes only. These tables will show how the load carrying abilities of your tires vary according to air pressure
settings. Please refer to the Federal tag (FIG. 1) for proper tire air pressure for your motor home.
TIRE MAINTENANCE
When cleaning tires, try to use a tire-cleaning agent. Never use any cleaner that contains solvents. Solvents will draw
oil from tires and cause them to prematurely crack. Inspect your tires prior to each trip, looking for bulges or cracks in
the sidewalls.
When storing your recreational vehicle for long periods of time, you should completely unload the vehicle so that a
minimum weight will be placed on the tires. Make sure the tires are inflated to the recommended operating inflation
pressure. Avoid moving the vehicle during extremely cold weather. Move the vehicle at least every three months to
prevent ozone cracking in the tire bulge area as well as “flat spotting” from prolonged strain of sidewall and tread
deflection. Make sure you check the inflation and adjust to the recommended operating pressure before putting the
vehicle back into service.
Tire life expectancy varies. Some tires reach their life expectancy and may need to be replaced in as little as six years
regardless of tread wear. Please refer to the tire manufacturer for recommendations in regard to tire life expectancy.