We love travelling in cars, vans and motorhomes for the freedom and comfort they give us. And we love the fact we can bring lots of things along. But when we pack our lives into our cars or load the caravan for a trip, we often forget to think about how much additional weight we are adding. Tyres can’t bear unlimited weight! Just because your van has enough space to fit that bike, boat, and a cooler packed with food doesn’t mean your tyres can cope with the task. The same applies to an SUV towing a trailer or a car with a roof box piled high for a road trip.
For a safe trip, it is crucial not to overload your vehicle. It is very important to adjust your tyre pressure depending on the weight you have added. We’ll tell how to avoid overloading tyres when on a long trip.
Why is overloading dangerous?
The tyre is doing very hard work supporting the total weight of the vehicle and withstanding deformations, speed, heat and incredible forces. Heat causes exfoliation and separation of tread pieces as well as sidewall cords damage that can progress even after the extra load is removed. If your vehicle is overloaded then these forces are multiplied. Every tyre has a specific weight limit you shouldn’t exceed or it will simply fail – think about what will happen if you experience a blow at in your hugely overloaded car at high speed on a busy motorway.
Consistently using tyres on the top of their weight limit degrades tyres the same as overloading them for a short time. If a tyre has already been underinflated or damaged, even a small extra load can lead to a blowout.
How can overloading be avoided?
1. Know your limits. At first, you need to find out how much weight your tyres need to support. This information can be found in your cars owner’s manual or on the sticker placed on the driver’s doorjamb. Then check the tyre’s maximum load capacity on its sidewall. It must be equal to or more than the total load you are going to bring along. In this case, your tyres must be inflated to their maximum pressure (this information can also be found in the owner’s manual), which MUSTN’T be exceeded. Let’s assume that information on the tyre’s sidewall says “Max 2,000 lb @ 35 psi”. It means that the tyre can carry the maximum of 2,000 pounds being inflated to no more than 35 pounds per square inch. It also means that, once your car has 4 tyres, the total weight of the car and baggage mustn’t exceed 8,000 pounds.
If in doubt refer to Tyresafe’s car tyre or caravan tyre pressure calculators.
2. Choose tyres accordingly. If you need to haul heavy loads, consider changing your tyres for another set with the same size but a higher load capacity or slightly larger tyres. Consult a tyre specialist before opting for larger tyres. Another solution is to increase pressure in tyres if their maximum pressure limit allows doing so. For your RV, use only caravan tyres that match your owner manual’s specifications.
3. Choose motorhome wisely. If you are going to rent a recreational vehicle, do it with your prospective load in mind. Modern RVs vary in design, size, and loading capacity. Some of them have equipment for carrying a certain type of cargo like a motorcycle, bikes, or a boat.