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Free — And Smoother — Wheeling

Rethink Wheel Balance When It Comes To Trailer Tires.

If you want a high-yielding crop, then that quest for quality begins with a soil test. If you want high-performing tires, the safest operation, and the most reliability from the vehicle or trailer, that journey starts with having the tires balanced.

Many think of tire balance as strictly for ride comfort, but there is much more going on as any tire rolls down the road.

Though it’s commonplace to have passenger car and light truck tires balanced, it is just as important to balance those on trailers and wagons if they’ll be driven at 30 mph or faster. 

The Forces Of Imbalance In A Tire

When a wheel rotates, any difference in mass creates the tendency for the heavier area to move away from its axis of rotation or to be flung out. As a tire rolls down the road, it does not stay completely round. A portion of the tread (that contacts the surface) flattens out as the weight of the vehicle is placed on it. 

As that part of the tire rolls away from the surface, another contact patch undergoes deformation. An exaggerated example is a tire that is very low on air. The bottom is flattened while the rest of the tire is round. With less drama, that is what occurs to every tire as it rolls.

For this reason, inflation pressure is critical since it not only supports the weight of the load but also limits the amount of tread that flattens as it rolls. 

When the rotating mass of the wheel and tire assembly are out of equilibrium, then it wants to hop, wobble, and bounce. As the road speed is raised, these actions are increased and magnified.

Impacts More Than Tire Performance

That’s why it’s important to balance trailer tires since the dynamics of rotational imbalance affects them, even though you may not feel it. By the time a nutrition deficiency is visual in a plant, the yield loss has already occurred. By the time a tire vibration reaches your senses, it is degrading many components.

Out-of-balance tires cause excessive wear in wheel bearings, suspension parts, spring shackles, shock absorbers, and the tires themselves. Plus, the tire may experience cupping, uneven wear, and tread or ply separation. This is especially true with trailer tires. Trailers will also bounce more when unloaded, shake themselves apart, and transmit that motion into the hitch and the tow vehicle. As it pertains to an emergency braking situation, a properly balanced trailer tire will decrease the stopping distance and provide much better control. 

New Tires Should Always Be Balanced

New tires should always be dynamically (spun) balanced and, if possible, put on a machine that provides a road force test. This is where a roller is pressed against the tire to simulate the deformation that occurs when in use. There is an effect identified as radial force run-out that allows a tire to bounce down the road even though it is in mass equilibrium. A road force balance compensates for that.

As a tire wears, it will impact the balance. At one-half tread life, I like to get tires rebalanced. The cost of balancing is very low, and it provides better driving dynamics, decreases wear on the tire and vehicle or trailer, and improves safety. 

A good technician will acknowledge the amount of weight required. If excessive (more than 2 ounces on one side), the technician will break the bead and rotate the tire on the rim 90° and then retest. This process is repeated until the least amount of weight is required.

When better tires are new, they have a paint or ink dot to identify the mounting in relation to the valve stem. If you see a wheel loaded with lead weights, then either the mechanic who balanced it was poorly trained, the machine was out of calibration, the rim was bent, or the tire wasn’t well made.

I also like to carry with me a tire crayon. If I get a flat on the road, I can mark the position of the valve stem and the weights. This way, the tire can be put back on the rim in the exact location if the shop fixing it does not have a balancer that I trust.

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