Which tires for overlanding: Mud tires Vs all-terrain tires

Mud tires (M/T) or all-terrain  tires (A/T) for traveling by 4×4 ?

To describe 4×4 tires, it’s more accurate to represent them as an off-road / on-road percentage.

• Road tires called H/T for Highway-Terrain are generally the original equipment tires on your 4×4. They are 80% road and 20% off-road. It is therefore strongly advised to change them when traveling with a 4×4.
• An off-road tire generally called A/T for All-Terrain Tyre will be 50% road and 50% off-road.
• Mud tires called M/T for Mud Terrain will be 80% off-road and 20% road. They usually have 3 plies when the A/T tires have only 2 plies. The plies are layers of Kevlar, nylon or polyester synthetic fabric covering the entire carcass.

For traveling, only A/T and M/T type tires are recommended. In addition to the advantage of the plies, the M/T tire has large studs that evacuate mud better, cling better to rocks and do not let gravel stick to the tire. It’s true that it’s noisier on the road and its studs are a disadvantage when braking and cornering on the road. The blanks are better protected which will reduce the risk of punctures. There is still the question of sand: if the M/T’s studs are not a real advantage, it will still be chosen to ride at very low pressure because of its three plies and sturdy flanks. In fact, the studs will tend to “dig” into the sand. Don’t forget that our advice is for travelers, not Dakar riders. We can’t change tires every night. The M/T tire will therefore remain the best tire for all off-road terrain. If your routes are mainly on asphalt roads or well-maintained tracks, lean towards A/T tires with increased longevity.

A/T vs. M/T tire comparative table

Ideal 4×4 tire size for traveling

Normally, your vehicle will be equipped with approximately 31-inch tires.  It is advisable to have 32.8 inch or 33 inch tires for 4×4 travel.

Larger tires help maintain ground clearance (especially at low pressure). On the road, the car will be 2.5 cm taller with a 33-inch tire (add 5 cm for the lift kit, which will allow you to install larger tires) but in reality, in soft sand or deep mud, you will lower the tire pressure significantly and the tire will “regain” its original size or get closer to it.

Be careful, a 33-inch tire on a Toyota Hilux for example, requires some modifications: a 4 or 5 cm lift kit and a few blows with a mallet so that the wheels do not touch. Don’t forget that all your modifications must remain legal and conform to the legislation of your country. Also be careful with modifications that could have serious consequences in case of an accident with your insurer, you may not be covered.

Above 35 inches, the 4×4 requires a lot of modifications.

How to read the size of a tire and get its size in inches?

We will take the example of the tires equipped on our 4×4: 285/75 R16 113 Q

• 285 : corresponds to the width of the tyre in mm. Here 285mm wide.
• 75 : corresponds to the height of the tire. It is a relation in % between the height of the sidewall and the section width of the tyre. In our example, the sidewall height equals 75% of the width of the tire. The higher the ratio, the higher the height of the tire.
• R16 : corresponds to the inside diameter of the tire in inches (or the rim diameter). Here, 16 inches.
• 113 : corresponds to the load index. Here, the maximum load the tire can support when inflated to maximum pressure is 1150 kg (index 113).
• Q : corresponds to the speed index and indicates the maximum speed at which a tire is certified to be able to support a load safely. For an index Q, the maximum speed is 160km/h.

To calculate the size of his tire in inches, you can use this site: https://tiresize.com/converter/

Finally, here is a link for load index and speed index matches: https://www.tyres-pneus-online.co.uk/load-and-speed-indexes-advice.html

Choice of rims for a 4×4 trip

Avoid “low-profile” rims for off-roading. Your first shock absorbers are your tires. You need a better ratio for the tire than for the rim. We will therefore use 15 or 16 inch rims, 17 inches being the absolute limit. If your car is equipped with 18-inch rims as standard, you have a real highway 4×4 with nice brake calipers. You will hardly make this car a vehicle for overlanding.

Steel or aluminium rims?

• If the steel rims (also known as taule steel rims) are more fragile, with a hammer and a good hand, they can be repaired quite easily. They are much cheaper.
• Aluminum rims disperse heat better, are lighter. They can withstand a rather important shock but for very violent shocks, they will be irreparable.

If you often ride at very low pressure in mud or sand, be interested in the “beadlock” system that will prevent the wheel from coming off the road. Beadlock rims block the tyre bead on the rim. Beadlocks are recommended for pressures below 8 or 10 psi and only for relatively frequent use. Otherwise, just be careful to drive in a straight line until you get out of a very soft sand passage and reinflate the tires right afterwards.

Our choice: M/T tires and steel rim

“The choice was easy because we use our 4×4 (Mr Wolf) for exploration: often we don’t know the state of the track before going there so it’s better to equip for the worst! We bought 4 MUD tires and no regrets so far! Already 7000km of track in Kyrgyzstan, no punctures and above all, it goes everywhere! 

The difference in noise between A/T and M/T is audible but we get used to it quickly. We have steel rims and they do very well!

Finally, regarding tire size, we have 285/75R16 (equivalent to 32.8 inches) and the 4×4 is raised by 5cm.”

Victor & Olivia – OunTravela