How Do I know What Size Wheels and/or Tires Will Fit My Trailer?

Wheels and Tires = Safety

The tires on your trailer should be replaced regularly. Even when not travelling, they age due to UV exposure.

What if I can’t find an owners manual for my trailer online?

You want wheels as big as your trailer can accommodate and still leave enough clearance in the wheel well for 1) changing to a spare on the side of the road, and 2) allowing vertical travel within the wheel well when the suspension is bouncing.. It makes for better wear on the tires and a higher trailer clearance.

Measure the hub for the pilot hole diameter; that and the number of bolts will give you a starting point. If the original wheels are still on the trailer, you want to replicate them as closely as possible. If the trailer has no wheels, or you think the ones that are on it are incorrect, measure the bolt circle (the distance between the center of the hub and the center of one bolt multiplied by 2) and the inner wheel well carefully to determine the overall size it can accommodate when you include tires, and check to see if the wheels will require an inset or offset.

Why do some of your 15” and 16” wheels come in two different widths?

While tire radiuses are measured in inches, tire sizes are now in metric. Vintage trailer sizes and weights vary dramatically, and many have wheel wells that can’t accommodate a full size wheel and tire. The narrower wheels take narrower tires.

How do I know the wheels I want are strong enough to support my trailer?

Be sure to check the wheels’ weight ratings to ensure they can carry the load adequately.

My trailer’s wheels have split rims. Can I just get new ones?

Very few tire stores are willing to work on split rims because of the danger to employees when trying to change them.

I have a very small/very large trailer. Do you have wheels small/large enough to fit?

We carry wheels in 13”, 14”, 15”, and 16” diameters.

OK, I’m all set for wheels. What tires should I look for?

Tire construction has greatly improved throughout the years, so don’t use your old tires as guides for selecting new ones. Select the radius based on the circumference of your wheels. While tire radiuses are measured in inches, tire sizes are now in metric:

The first number = the width of the tire in millimeters at the widest part of the tire, not at the tread. You need to know this when calculating if the tire will fit in the wheel well.

The second number = the height of the sidewall in millimeters as a percent of the width of the tire at the widest part

The third number = the opening in the tire in inches

So a 205/75/15 tire is 205 mm wide at the widest part, the sidewall is 153 mm tall (75% of 205), and has a 15” radius

The best type of tire is an ST, or Special Trailer tire, followed by an LT, or Light Truck tire.

Ply rating is how much weight the tire can carry. Light Truck and Special Trailer tires use load ranges that ascend in alphabetical order (letters further along in the alphabet identify stronger tires that can withstand higher inflation pressures and carry heavier loads).

Load Range B = 4 ply rating, maximum 35 psi load pressure

Load Range C = 6 ply rating, maximum 50 psi load pressure

Load Range D = 8 ply rating, maximum 65 psi load pressure

Load Range E = 10 ply rating, maximum 80 psi load pressure

We do not recommend passenger tires for vintage trailers - they don’t have the correct sidewall construction. more UV protectant so they don't rot as quickly in the sun

Trailer tires have more rigid sidewalls so they tow better and can tolerate the sway on the road. They also have more UV protectant so they don't rot as quickly in the sun.

How about radial vs bias ply tires?

Older trailer tires were bias ply. Today, most are radial. We recommend radial tires in all situations.

How do I know what size tires to buy?

Can I put white wall tires on my trailer?

White walls certainly enhance the appearance of a vintage trailer! Please check our website for the sizes we currently carry.

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