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.

tire cover
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:

Tire Diameter

Tire Size

34'

FITS ALL 19.5' WHEELS





32 1/4"

7.50 X 16

315 70R 15

255 85R 16





31 1/4"

7.00 x 16

7.60 x 15

265 75R 15

7.50 x 15

H78 x 16

245 75R 16

10 x 16.5

255 70R 16

235 85R 16

10 x 17.5

265 75R 16

215 85R 16

8.00 x 17.5

275 70R 16

9.50 R 16.5





29 3/4"

6.50 x 16

9.50 R 15

255 75R 15

9.00 x 15

9.50 x 16.5

950 75R 15

7.00 x 15

8.75 x 16.5

235 75R 16

L78 x 15

7.00 x 17.5

225 75R 16

9.15 x 15


205 75R 16





29"

6.00 x 16

8.55 x 15

225 75R 15

8.45 x 15

7.10 x 15

235 75R 15

H70 x 15

8.25 x 15

235 75R XL

J78 x15

8.85 x 15

245 70R 15

J78 x14

8.85 x 14

235 70R 16


8.00 x 16.5

9.00 X 16.5





28"

8.55 x 14

7.35 x 15

215 75R 14

8.00 x 15

8.15 x 15

225 70R 15

7.75 x 15

H78 x 15

215 75R 15

8.50 x 14

8.75 x 16

235 70R 15



235 60R 16





27"

6.50 x 15

7.34 x 14

205 75R 14

7.75 x 14

8.25 x 14

205 75R 15

9.70 x 15

7.00 x 14

195 75R 15

F78 x 14

8.00 x 14

215 70R 15

E78 x 14

7.00 x 14.5

225 70R 14

G78 x 14

7.50 x 14

255 60R 15

F78 x 15

8.50R 14






25 1/2"

7.00 x 13

205 70R 14

185 75R 13

6.50 x 13

215 6OR 15

195 70R 14

6.95 x 14

215 6OR 16

175 80R 14

245 60R 14

215 70R 14

195 75R 14

245 50R 16

235 60R 14

185 80R 14

165 80R 15

245 60R 16

155 80R 15





24"

6.00 x 13

B78 x 13

155 R 13

165 80R 13

185 80R 13

175 80R 13

195 70R 13

165 80R 14

155 80R 14

185 70R 14

205 60R 14

195 60R 15

225 60R 14

215 60R 14

205 60R 15

215 50R 15

225 50R 16

225

245 60R 15

245 45R 16






21 1/2"

4.50 x 12

4.00 x 12

6.00 x 9

5.30 x 12

4.80x12

6.90 x 9


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

Cover Size

Tire Diameter

Tire Fit






SIZE 1

LARGE

33"-35"

ALL 19.5" WHEELS






SIZE 2

MEDIUM

30"-32"

7.00 x 15

8.00 x 16.5

265 75R 15

7.50 x 15

8.75 x 16.5

950 75R 15

7.60 x 15

9.00 x 16.5

255 70R 16

9.00 x 15

9.50 R 16.5

265 75R 16

9.15 x 15

9.50 x 16.5

275 70R 16

F78 x 15

10.0 x 16.5

225 75R 16

L78 x15

7.0 x17.5

205 75R 16

H78 x15

8.0 x17.5

215 85R 16

6.50 x 16

10.0 x 17.5

235 85R 16

7.00 x 16


245 75R 16

7.50 x 16

255 75R 15

255 85R 16






SIZE 3

SMALL

27"-29"

7.00 x 14

7.10 x 15

205 75R 14

7.35 x 14

7.35 x 15

215 75R 14

7.50 x 14

7.75 x 15

225 70R 14

7.75 x 14

8.00 x 15

195 75R 15

8.00 x 14

8.15 x 15

205 75R 15

8.25 x 14

8.25 x 15

215 70R 15

8.50 x14

8.45 x 15

215 75R 15

8.55 x 14

8.55 x 15

225 70R 15

8.85 x 14

8.85 x 15

225 75R 15

E78 x 14

9.70 x 15

235 70R 15

F78 x 14

H70 x 15

235 75R XL

G78 x 14

H78 x 15

235 75R 15

J78 x 14

J78 x 15

255 60R 15

7.00 x 14.5

6.00 x 16

275 60R 16

6.50 x 15

8.75 x 16

850 R 14






SIZE 4

XS

24"-26"

6.00 x 13

155 80R 14

235 60R 14

6.50 x 13

165 80R 14

245 60R 14

7.00 x 13

175 80R 14

155 80R 15

B78 x 13

185 70R 14

165 80R 15

6.95 x 14

185 80R 14

195 75R 15


195 70R 14

195 60R 15

165 80R 13

195 75R 14

205 60R 15

175 80R 13

205 60R 14

215 50R 15

185 75R 13

205 70R 14

215 60R 15

185 80R 13

215 60R 14

225 50R 15

195 70R 13

215 70R 14

245 50R 15

155 80R 13

225 60R 14

245 60R 15






SIZE 5

MINI

18"-22"

19"-22"

5.30 x 12

20.0 x 8 x10


5.70 x 8

20.5 x 8 x 10







SIZE XL

36"-39"

FITS MOST DIESEL CHASSIS

255 / 70R






SIZE BUS

GIANT

40"-42"

FITS MOST BUS CHASSIS WITH 22.5" WHEELS

275 / 70R / 22.5 275 / 80R / 22.5 255/80R






SIZE OS

_

43"-45"

FITS MOST BUS CHASSIS WITH 24.5" WHEELS

295 / 75R / 22.5


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

spare tire cover 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.

Final Word

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.