What is the difference between a tire cover and tire guard?
Both types of tire covers protect your tires against the damaging effects of UV Rays and falling debris, such as bird droppings. They are made of heavy-duty vinyl with an elastic cord used to secure them to the tire. The two major manufacturers of this type of cover are Adco Products and Classic Accessories.
The difference is when they are used. RV and van tire covers are installed on the spare wheel and tire when it is mounted on the vehicle while traveling (e.g. covers for Jeep wheels and tires that are mounted on the rear door.)
RV tire guards are designed to cover the wheels of a vehicle that remain on the ground while the RV, truck, or van is being stored.
Measuring for Spare Tire Covers
Spare tire covers need to fit tightly to prevent them from coming off and to offer maximum protection for the tire. So it is important that you purchase the correct size for the tire you want to cover. There are multiple sizes available, and they are all based on the diameter of the TIRE (not the wheel.) Any given wheel diameter can ultimately have various exterior tire diameters, depending on the profile of the installed tire.
Use the chart below to determine which size of spare tire cover you will need for your tire:
Adco Covers has spare tire covers in white and black, as well as steel diamond plate and camouflage motifs. A USA Flag design is also available in a limited number of sizes.
Classic Accessories makes spare tire covers in both a custom fit in white only and universal fit in both white and black. Both will fit Jeep Wranglers and other vehicles with rear tire carrier mounts.
Measuring for RV Tire Guards
RV Tyre Guards are like tire covers, but they do not cover the small section of tire tread on the ground. To begin the installation, these covers are slipped on over the top of the tire to start. Then, they are secured by a bungee cord connecting the two tabs on either side of the tread cutout at the bottom of the tire.
The other difference with tire guards is that they are available not only for single axle configurations but also for trailers that have double and triple axle setups.
But whatever axle configuration you have, Tire Guards are sized in the same manner as for spare tire covers, matching the diameter of the tire. Below is a chart of tire guard fits
Adco Products offers a premium version called the Ultra Tyre Gard that features a two-tone tan deluxe design.
Classic Accessories, the other major RV cover manufacturer, calls their Tyre Guards "RV Wheel Covers"
There is an additional way to protect your RV, truck, or van tires that remain on the vehicle during storage. Place a small sheet of heavy plastic under the tread of your camper, RV, or truck camper to prevent moisture from seeping up into the rubber. This barrier prevents premature tread separation from rotten
Calculating the Tire Diameter
If you are unable to physically measure your tire but know its size, there is also a math calculation you can perform to determine the overall tire diameter.
The first number in the size of a metric tire is the width in millimeters. To come up with a result in inches, you will have to start by dividing this number by 25.4 to convert to inches (there are 25.4 mm per inch.)
The second number on a metric tire is used to determine the sidewall height. The sidewall height is expressed as a percentage of the width of the tire and the second number is the percentage value. So the calculated height of a 285/75/R16 tire is 75% of 285mm = 213.75 mm (or 8.4" when divided by 25.4.)
The third number (usually with "R" in front of it) is the diameter of the wheel.
So, once you have the height of the tire, simply add it twice (there is a tire on both sides of the wheel) to the tire diameter. This will calculate the diameter of the tire for you.
Example: for a 285/75R16 Tire, the calculation is:
(285 / 25.4 X .75) x 2 + 16 = 32.8 inches tall.
Motorhome, RV, and Trailer Tires can be a huge cost investment when you need to buy replacement tires because they are not safe. Since they are not generally used daily, the need for replacement is generally triggered by a failure in the sidewall, not by a worn tread.
Using tire covers and tire guards to prevent the sun and other elements from drying out or damaging the sidewall rubber can improve the tire's longevity. Covers will eliminate sidewall cracking and separation of the various tire ply’s from each other.
More from RV Part Shop
RV Part Shop carries a complete line of RV Parts and Truck Parts and Accessories, including mud flaps, tonneau covers, and bed liners/mats. We also offer a full line of trailer tires, trailer wheels, RV wheel simulators, and tire accessories.