How to Install Trailer Wheels: A Step-by-Step Guide for Beginners

1. Chock the wheels on the opposite side of the trailer.

2. Loosen the lug nuts.

3. Lift and secure the trailer with jack stands.

4. Remove the old wheel and clean the hub.

5. Install the new wheel and torque the lug nuts.

Understanding Trailer Tire Sizing

Trailer tire sizing information is found on the sidewall and tells you everything you need to know about fitment and construction.

For example, a tire labeled ST205/75R15 breaks down as follows:

• ST indicates it is a Specialty Trailer tire

• 205 is the tire width in millimeters

• 75 is the aspect ratio, meaning the sidewall height is 75% of the tire’s width

• R denotes radial construction (a D would indicate bias-ply)

• 15 is the wheel diameter in inches

Checking Tire Load Ratings

In this case, the tire shown is:

• Load Range C / 6-ply rated

• Maximum load capacity of 1,820 lbs

• Maximum air pressure of 50 PSI

Always measure tire pressure when the tire is at ambient temperature. Choosing the correct load rating is essential for tire longevity and towing safety.

Verifying Wheel Bolt Patterns

Once your tire size is confirmed, it’s time to verify the wheel’s bolt pattern.

• 4-lug wheels are measured center-to-center across opposite lug holes (commonly 4 on 4")

• 5-lug wheels are measured from the outside edge of one lug hole to the center of the lug hole across from it (commonly 5 on 4.5")

• 6-lug wheels are measured center-to-center, skipping two lug holes (commonly 6 on 5.5")

• 8-lug wheels are measured center-to-center, skipping three lug holes (commonly 8 on 6.5")

Tools You’ll Need

Before starting, gather the following tools:

• Floor jack

• Jack stands rated for 2 tons or more

• Torque wrench capable of at least 100 ft-lbs

• Breaker bar or impact wrench

• Impact socket

• Tire pressure gauge

• Wire brush

Step-by-Step Installation

1. Chock the Wheels: Begin by chocking the wheels on the opposite side of the trailer. This prevents movement and significantly reduces the risk of an accident.

2. Loosen the Lug Nuts: With the trailer still on the ground, loosen the lug nuts using a breaker bar. If you’re using an impact wrench, you can wait until the trailer is lifted.

3. Lift the Trailer: Using a floor jack, lift the trailer at a sturdy point on the frame. Raise it just enough to get the wheel off the ground.

4. Secure with Jack Stands: Place jack stands under solid frame points, one in front of the axle and one behind it, for a single-axle trailer. Slowly lower the trailer onto the stands and confirm it is stable before continuing.

5. Remove the Old Wheel and Clean the Hub: Remove the lug nuts completely and take off the old wheel. Use a wire brush to clean the hub’s mating surface, removing corrosion and debris so the new wheel seats properly.

6. Installing the New Wheel: Mount the wheel onto the hub, install the center cap, and hand-thread the lug nuts to prevent cross-threading. Once hand-tight, snug them down using a breaker bar or impact wrench. Before lowering the trailer, check the tire pressure and inflate it to the PSI listed on the sidewall.

7. Lowering the Trailer and Torquing Lug Nuts: Lift the trailer slightly to remove the jack stands, then slowly lower it back onto the ground. Chock the wheel again for safety. Using a torque wrench, tighten the lug nuts to the manufacturer’s specified torque. For a 5-lug wheel, use a star pattern first, then follow with a circular pattern. This ensures even clamping force and proper wheel seating.