Article
WILL AN ALL-TERRAIN OR MUD-TERRAIN TYRE AFFECT YOUR VEHICLE’S FUEL ECONOMY?
2020-01-01
When it comes to buying off-road tyres, there’s little doubt that a Light Truck (LT) variant should be at the top of your shopping list, especially if you intend to:
- Drive off-road
- Tow a trailer, caravan or boat
- Heavily modify your vehicle with aftermarket accessories
Light Truck tyres have stronger carcasses, deeper treads, tougher compounds, and they’re capable of carrying heavier loads than their P-Metric equivalents. However, despite all these benefits, most Double-Cab vehicles, 4x4s and SUVs are factory fitted with P-Metric tyres due to economic reasons, and the fact that vehicle manufacturers have to compete on fuel economy.
In this regard, a common question amongst first-time off-road tyre buyers is: “Will an all-terrain or mud-terrain tyre affect my vehicle’s fuel economy?” The short answer is: Yes.
However, there’s more to the subject of fuel economy than just tread design.
WEIGHT AND STRENGTH
Although certain tread patterns are prone to a higher rolling resistance, the tyre’s overall mass has a greater impact on fuel consumption. Heavy tyres require more energy to turn, and in most cases, LT tyres are considerably heavier than P-Metrics.
Unbeknown to many vehicle owners (including tyre dealers), the vast majority of all-terrain tyres on the market are P-Metric variants. Although the tread pattern may suggest that it’s an off-road tyre, the truth is, most P-metric tyres have poor load-carrying abilities, limited puncture resistance, and little in the way of off-road durability.
Sadly, there’s no way around this. If you want a true off-road tyre that can handle off-road terrain without sustaining punctures, sidewall damage, or total tread destruction, you need to look for an all-terrain tyre that clearly displays the letters ‘LT’ on the sidewall; and with that, a slight increase in fuel consumption should be expected.
Naturally, if you decide to fit a larger tyre than the vehicle manufacturer’s recommended diameter, this too will have an effect on fuel economy.
In contrast, mud-terrain tyres are (by default) Light Truck tyres. It’s only in the all-terrain market that the confusion occurs, and that’s because the visual differences between a LT and P-Metric tyre are not always obvious. Aside from the lettering on the tyre’s sidewall, in every other way the two tyres may look identical.
Of course, if you were to carry both tyres, you would immediately feel that the LT is heavier, in some cases, up to 40% heavier than a P-Metric product. Hence, the added fuel use.
On the subject of mud-terrains: This is where tread design will play a far greater role in fuel economy. This is because an aggressive tread pattern will add further drag to the tyre’s rolling resistance.
Finally, one should also keep in mind that not all LT tyres are constructed equally, as other factors such as compound quality, steel quality, and nylon-cord quality all come into play. You can read more about that here.
On that note, the decision to replace your factory-fitted P-metric tyres with a Light Truck all-terrain, should include a pros and cons list of doing so. Here’s what you should expect…
- A slight (but noticeable) decrease in fuel economy
- A significant increase in puncture resistance
- Far lesser chance of incurring sidewall damage
- Less chance of sustaining heat damage
- A greater load-carrying capacity
- Vast improvement in off-road durability
- Potentially longer tread life due to a deeper tread pattern
- Better steering response