Tire care and electric vehicles

A few key differences in how EVs work mean that the choice of tire can have a direct impact on both how a vehicle performs and how long the tires will last.

Electric vehicle motors produce maximum torque from a standing stop and their batteries make them somewhat heavier than their combustion counterparts — both of which can lead to tires wearing faster. The fact that EVs are much more efficient, and they dramatically lower operational costs, means that tires become a much higher percentage of total costs. This is why tire selection, care and maintenance are so important for anyone running EVs in their fleet.

Energy efficient tires are an EV essential

A couple of factors play into the impact of tire performance on an EV’s range. These are tire pressure — the air inside a tire is what supports a vehicle’s weight — and something called rolling resistance: the amount of friction generated when a tire rolls against the road. Less friction means a lower battery drain and lower impact on a vehicle’s range. A tire’s weight, rigidity, tread design and quality of the rubber all play a part in rolling resistance.

Low rolling resistance tires are widely available — they also improve fuel efficiency for combustion-engine vehicles, though on a smaller scale. But reducing premature tire wear and optimizing range are two compelling reasons to consider a tire made specifically for EVs.

Torque, the biggest factor in EV tire wear

The factors that contribute to the potential for faster tire wear in electric vehicles are:

• EVs have snappier acceleration, with maximum torque available from zero RPM
• vehicles are 10 to 20 per cent heavier due to the weight of the battery

Side by side, an EV driven exactly the same way as a combustion vehicle should see minimal difference in tire wear, and certainly not more than comparing an IC vehicle with another with 10 per cent higher weight. Regardless of whether a vehicle is powered by electricity or gas/diesel fuel, the vehicle’s weight and powertrain are less of a factor in tire wear than driver behaviour, says Jack McClure, segment manager for North American passenger and light truck tires at Sailun Tire Americas. If a driver regularly accelerates or brakes aggressively, that behaviour combined with the added weight and torque of an EV can make premature tire wear more likely. So the fact that EVs have gained a reputation for faster tire wear is mainly down to driver habit.

Several commercial vehicle manufacturers program torque limiters into their electric vehicles’ control units but fleets can benefit from training drivers to be gentle on the accelerator.

Frequent pressure checks and early rotations

Driver training and frequent walkarounds are key elements of an electrified fleet’s tire maintenance strategy. EVs tend to run on much higher tire pressures to boost efficiency: 45 PSI versus 30 to 35 PSI on a combustion vehicle. Also, knowing if your EV is front-wheel drive, rear-wheel drive or all-wheel drive is critical. Two-wheel drive vehicles will wear out their driven wheels much faster due to the combination of power transfer and braking all on the same tires. An all-wheel drive EV will spread tire wear much more evenly.

 “Knowing proper air pressures, what your tread depths are at regular rotations and just having walkarounds on your vehicle will go a long way to maintaining tire performance” says David Pulla, manager of national sales for Sailun Tire Americas. “[Rotations] anywhere in that 5,000 to 10,000-kilometre range are recommended will always benefit the consumer.” While those are the same intervals as for combustion engine vehicles, experts including Pulla recommend an “earlier is better” approach to tire inspection and rotation for any newly-deployed fleet EVs.

Learn more: EV versus ICE walkaround and maintenance lists

Tips for replacing EV tires

Many EVs are sold with tires specifically designed for their model, but choosing replacement tires might require a conversation between you and your fleet dealer or tire dealer. Account for factors like the vehicle’s daily workload or range and the climate where the vehicle is operating. Here are some other things to consider.

Consider tires designed for EVs

Most standard tires will work on EVs, but they may not maximize efficiency or quietness. As a result, most major tire manufacturers now sell tires marketed specifically for use on electric vehicles. That list includes Bridgestone, Continental, Goodyear, Hankook, Michelin, Nokian, Pirelli and Sailun. 

Know what you’re paying for

The EV tire offering continues to grow as manufacturers fine-tune innovations. Each of these properties signifies additional cost and an EV-specific tire can cost 30 to 40 per cent more than a comparable standard tire.

• New rubber compounds are meant to increase durability. 
• Rolling resistance is lowered by reducing tire diameter and making tires more rigid, sometimes by adding silica to rubber. 
• New tread patterns are designed to stand up to the torque and to reduce noise. 
• Some tires even include a foam insert to keep things extra quiet — EVs are so much quieter than combustion vehicles that road noise can be more noticeable. 

Fit tires matching the OEM’s load rating

Since EVs are heavier, they tend to require tires with higher load ratings, also increasing replacement cost. It is a legal requirement to match tires to the load rating specified by the OEM — ignoring that requirement may void a vehicle’s insurance policy.

Tire type is also important

Soft compound performance tires on combustion vehicles are often designed to last less than 30,000 kilometres. Pay attention to the Uniform Tire Quality Gauge (UTQG) treadwear rating on the side of the tire prior to purchase – it’s an accurate guide to the lifespan of the tire.

Don’t skip the winter tires

Experts strongly recommend the use of winter tires in most parts of Canada, even where it’s not compulsory. Follow the manufacturer’s certified tire specifications when fitting winter tires, especially the load rating.

The right tire and regular spot checks can save money

Remember that tires are really the only significant maintenance cost on an electric vehicle: EVs dramatically reduce brake wear (by 80 per cent or more) and there are no oil changes. Tires may represent 90 per cent of the maintenance budget over 10 years, but overall maintenance costs are still drastically lower than for a combustion-engine vehicle. At the same time, the right tire can have a big impact on EV fuel efficiency.

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