RV Tire Basics

Safe and dependable tires are critical to enjoying RV camping. RV Tire Basics includes how to read tire markings and how to maintain tires for travel trailers, motorhomes, and other recreational vehicles. Let’s get started.

RV Tire Markings

Think of your vehicle tires as air containers. Sealed inside is pressurized air that makes the tires firm but not rigid. Tires are constructed in layers to support the vehicle weight, absorb road shocks, provide traction and braking, and maintain direction of travel. 

What’s the difference between tires? You can find out yourself by reading required markings on the side of the tire (refer to the illustration).

1 = Tire width (in millimeters)

2 = Aspect ratio (% of a tire section width to height)

3 = Tire construction (Radial or Bias-ply)

4 = Rim diameter (in inches)

5 = Load index (measurement of load capacity; refer to manufacturer’s index chart)

6 = Speed symbol (maximum speed of tire design; refer to manufacturer’s symbol chart)

In addition, this code is preceded by “P” for a passenger tire, “ST” for the special trailer, or “LT” for light truck design.

The other code on your tire that you should check is the DOT Code on the sidewall, specifically the last four digits.

They indicate when the tire was manufactured; the first two digits are the WEEK number and the last two digits indicate the YEAR of manufacture.

If the DOT code ends in “1618” the tire was manufactured during the 16th week (mid-April) of 2018. (Note that some tire manufacturers include additional codes, such as “M16K 18RX”.)

Most important, refer to the trailer, truck, motorhome, or other vehicle’s owner’s manual for the manufacturer’s recommended tire size, rating, and air pressure.

RV Tire Maintenance

To keep your RV camping safer, make sure you read and maintain your vehicle(s) tires. Here are some RV tire maintenance tips:

• Manufacturers recommend that tires not be used beyond 6-10 years of age. Tires parked in sunlight without cover are the most susceptible to sun aging and degradation.
• Look for checking and cracking on RV tires; trailer tires are often neglected between camping seasons.
• Maintain tire pressure following the vehicle and tire manufacturer instructions. If in doubt, ask a reputable tire retailer to recommend tire pressure.
• Don’t install passenger tires (P) on to a motorhome, towing pickup, van camper, or other light truck (LT) vehicle.
• Always carry a spare tire. Some RVs are not equipped with them from the manufacturer to save weight and space (and money!). Road service can install your tire for you, but may not have a specialty tire in stock to bring you.
• On a camping trip, check your tires once a day for inflation, damage, and wear.
• Know where your tire jack and lug wrench are on your RV, if any.
• If you’ve purchased a new or new-to-you RV, make sure you know how to change a tire on it in an emergency.
• If your RV or tow vehicle has dual tires on the rear axle (dually), make sure you know how to check tire pressure on the inside tires.
• Periodically check tread depth on all tires, which should be at least 2/32″ (1.6mm). If you don’t have a tread wear indicator, insert a Lincoln penny upside down in the tread; if you can see the top of Abe’s head, the tread is insufficient.
• Rotate your RV tires (or have them rotated) every 5,000 to 8,000 miles per the vehicle manufacturer’s recommendation.
• Don’t overload your RV. Excessive weight in your motorhome, trailer, camper, or tow vehicle and put excessive stress on tires.
• Replace tires with the same tire size, type, and speed rating as recommended by the manufacturer. If not known, ask a trusted tire retailer.
• Consider an RV emergency roadside assistance insurance policy.
• Keep a frugal maintenance notebook with tire specifications and maintenance information.

RV Tire Basics and Safety Tips (Video)