Tech Talk

Stop wasting so much money: tyre pressures must match the load

We use runners for running, slippers for relaxing, work boots for work, and flip flops for the beach. If you want to walk on soft snow, use snowshoes that spread the load over a large area. 

Ducks have big flat feet, as do camels for soft ground.  We all know horses and cows sink into paddocks.

Race car tyre pressure wins or loses races. Bathurst is lost if tyre pressures are one psi wrong. Desert racers run low pressures. Trucks on the Tanami stop and lower tyre pressures. Four-wheel drivers know the benefits of low-pressure tyres when off road.

Even bicycle racers adjust tyre pressures, to tune traction to the track.

Every car manufacturer recommends a correct pressure for each model. Tyre pressures are super important.

Michelin recommends matching tyre pressures to the tyre load. Michelin produced charts showing tyre wear loss when over or under inflated. Load to Inflation tables are produced by every tyre manufacturer and tyre association recommending the correct tyre pressure for the load.

The NHVR PBS Tyre review recommended the following pressures for 11R22.5 tyres for typical Aussie maximum loads: 120 psi for steers, 75 psi for tandem drives, and 55 psi for tri axle trailers.

All of this proves running one single tyre pressure on all of our trucks reduces safety, costs truck owners a lot of money, and damages our roads and world.

So, what are the facts. Truck tyre footprints, where the rubber meets the road, is an engineering masterpiece. 

Engineers spend a fortune getting the steel cord placement, strength, rubber thickness and profile, and placement exactly right to spread the load evenly over the footprint area.   

If the load is concentrated in one area, the tread will squirm as it rolls around and wear will increase. This ideal footprint only happens when the tyre-pressure matches the tyre load.

What should you do? Adjust your tyre pressures every time the load changes. When heavy, you need lots of tyre pressure. When empty only a little pressure is needed. And on gravel optimal tyre pressures are 60 per cent of optimal highway pressure.

What are the benefits? Substantially better tyre life. Our customers report tyre life increases at least 30 per cent. Saving one tyre in three saves a lot of money over the life of the truck. 

Downtime reduces because tyres don’t need changing so often. Less punctures save dangerous and costly roadside tyre changing. Traction increases which reduces stopping distances and improves trailer tracking.

Trailer swing is substantially reduced increasing safety for all road users. 

Over inflation increases wear and tear on every truck component, from wheel bearings to diffs to intercoolers to suspension seats. Running the optimal tyre pressure increases the life of the entire truck, while substantially reducing maintenance and downtime costs. The savings are simply huge.

Obviously, changing tyre pressures manually is not effective. Central Tyre Inflation is a commercially available add on product that has been around for decades. A dash mounted tyre pressure display and control makes on the fly adjustment easy.  

Electronic controls automatically maintain any set pressure, including automatic re inflation of any tyre that has a puncture or air loss. This eliminates almost all blow outs, saving even more money. Simply push a button on the dash to adjust the tyre pressures. The benefits and systems have proven to significantly reduce costs and increases safety. Everyone wins.

We have written a white paper on Central Tyre Inflation and tyre pressures, that is a 120-page comprehensive document explaining all aspects of total tyre pressure management. 

Contact AIR CTI via either or via 03 51276128 for a free copy, or a chat.    

Additionally, a full million-kilometre guarantee, and money back guarantee backs up every AIR CTI total tyre pressure management system, ensuring your total vehicle cost is minimised.

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