THE DANGER OF USING THE WRONG WHEEL LOAD RATING?

HOW MUCH LOAD MUST EACH WHEEL SUPPORT?

When individual axle-load data is unavailable, the following formula can be used as a quick estimate:

Some vehicle manufacturers and heavy-duty applications use a larger safety margin, increasing the factor to 1.3.

Safety margins vary among manufacturers, vehicle types, and testing standards. This is therefore not a single mandatory formula used worldwide, but a conservative method for selecting an appropriate wheel load rating.

The vehicle's GVWR is normally shown on the vehicle identification label, commonly located inside the left- or right-front door frame. It may also be listed in the owner's manual or official technical documentation.

TRADITIONAL LOAD RATINGS NO LONGER FIT MANY EVS

Historically, many aftermarket wheel load ratings were developed around conventional internal-combustion passenger cars.

For a relatively light Japanese passenger car, a load rating of 690 kg per wheel is often sufficient.

China's new-energy vehicle industry, however, is developing extremely quickly. Large battery packs, bigger vehicle bodies, air suspension, and additional luxury equipment have pushed the GVWR of many new EVs and large new-energy SUVs beyond 3,000 kg.

For a vehicle with a GVWR of 3,000 kg, the calculation is:

This means that a vehicle in this weight class may require a load rating of approximately 900–975 kg per wheel. A traditional 690 kg wheel is no longer appropriate for this application.

In the Chinese market, we have seen wheels from some overseas aftermarket brands whose dimensions fit Chinese new-energy vehicles, while their load ratings are still based on conventional lightweight passenger cars.

This does not necessarily mean that the wheel itself is poorly made. It may simply mean that the original product range was never developed around the weight of today's Chinese new-energy vehicles.

FITTING THE CAR DOES NOT MEAN CARRYING THE CAR

Load mismatch can be understood with a simple comparison.

Imagine a person who weighs 250 kg wearing jeans designed for someone weighing no more than 150 kg.

They may be able to force the jeans on. Standing still or walking slowly may not cause immediate damage. But during strenuous movement, the probability of failure increases dramatically.

A wheel behaves in much the same way.

An under-rated wheel fitted to a heavy vehicle may show no obvious problem during ordinary driving. But repeated road impacts, fast cornering, emergency braking, and high-speed pothole strikes can generate forces far beyond the vehicle's static weight.

Over time, an insufficient load rating increases the risk of deformation, fatigue cracking, air loss, and even structural failure.

DO NOT ASK ONLY: “WILL IT FIT?”

Load rating must be checked carefully when selecting wheels for:

• Battery electric vehicles
• Plug-in hybrid vehicles
• Large SUVs
• Off-road vehicles
• MPVs and people carriers
• Vehicles with a high curb weight or GVWR

Before purchasing wheels, check the vehicle's GVWR and require the wheel manufacturer or brand to provide a clearly stated load rating for each wheel.

We are Makstton. From China.