AIR CTI - Central Tyre Inflation System FAQ

What is AIR CTI?
The AIR CTI is a Central Tyre Inflation System that enables the Transport Driver to Inflate and Deflate the Tyres of the Vehicle from within the Cabin As easily as pushing a button, whilst the Vehicle is still in motion.

How does it Work?
The Central Tyre Inflation System is designed to give you maximum tyre contact with the roadway to maximize you're use of the Tyre Tread to achieve optimum Traction and Braking in all conditions.

Will a Large Air Loss Affect my Brake System?
No. Every AIR CTI system uses a pressure protection valve (priority valve, hold back valve) to provide priority to the braking system. The system must be above 75 psi before air is used.

Is AIR CTI Beneficial in Sand, Stone, Mud or Gravel as well as Bitumen?
Yes. The AIR CTI Central Tyre Inflation System enables the Driver to Inflate and Deflate the Tyres of the Vehicle to compensate for the load and the road. Different Tyre pressures are used when the vehicle is loaded or empty, as well as for the different compounds of the road in dry and wet conditions. We refer to manufacturers Tyre Pressure Tables to enable up to date information on these recommended Pressure levels.

Is AIR CTI proven?
Central Tyre Inflation Systems have been used by Armies world wide since the 1940's, and has been used by both Military and Civilian workforces in many road conditions, including Rough, Muddy, Sandy and Gravel roads, and in wet and dry conditions in all Terrains.

Why Should Tyre Pressure Change?
You should change your tyre pressure to suite your load, the road or track conditions, whether Fully Loaded or Empty, and as deemed suitable for your Current Transport Needs. The Pressure should be changed to Maximize Traction and will assist you to Control your Momentum, your Braking and your Steering, giving you a Safer and more Comfortable Ride, with less Damage to the Vehicle and the Driver.

Isn't the Tyre Pressure Printed on the Tyre Correct?
Yes.This Pressure is the correct pressure to use for Highway roads at the maximum load that the tyre was designed for
AND NO! – Tyres are regularly used with less than their maximum load, and not always in Highway conditions, therefore the Tyre Pressure should be adjusted to reflect the conditions, such as the type of Road, whether the Truck is loaded or empty, and if weather conditions are wet or dry.

You Mean, Tyre Pressure should Change whenever the Load Changes?
Yes. To optimise tyre life and minimize wear and tear to both your tyres and your Truck, the tyre pressure should be changed to reflect the current conditions, such as road and load, and wet or dry. This is to achieve maximum traction. Remember – Change the load – Change the Tyre Pressure, and Change the Road – Change the Tyre Pressure.

That means virtually every Truck has too much Air Pressure most of the Time?
Yes. Too much tyre pressure is often used even when fully laden. You can refer to Manufacturers charts to find the optimum pressure to use, and AIR CTI helps you to control this pressure at the Push of a Button from the cabin whilst on the move. (According to Michelin, our standard maximm legal load on 11R x 22.5 tandem drive tyres should have only 85 to 90 psi,    Dependent upon the tyre model Used)

Does it really make that much Difference?
The smaller the tyre contact with the roadway the sooner the tyre will wear out (Pirelli states that a 20% over inflated tyre will wear out 10% quicker.) The Tyre Pressure affects the impact or absorption of the road conditions and Increases tyre and vehicle maintenance requirements, such as, the effects of corrugation or low traction, resulting in less vehicle control, less steering and braking ability, and will impact on the safety of your vehicle.

Why is Tyre Pressure so Important?
Too much pressure and the edge of the tyre lifts off the road, with pressure distribution concentrating towards the center of the tyre. Too low pressure, and the footprint lengthens, case flexing increases, and tread squirm increases. Either too high or too low will reduce handling and braking, increasing tyre wear, and will lead to uneven wear patterns. The tyre manufacture spent a lot of time and money designing a tyre to provide the best performance. A perfect tyre footprint, with full width contact, with equal pressure on every point of that contact area, and with minimal tread squirming. This can only happen at one pressure for each load. Remember – Change the load – Change the Tyre Pressure, and Change the Road – Change the Tyre Pressure.

What about Off Highway?
Rough roads will mean lower speeds, which translates into less tyre heat. Lower tyre pressure will benefit you on rough road operations. Lower pressures allow the tyre to flex more, absorbing a greater percentage of bumps and impacts. Impact reductions of up to one tenth have been demonstrated. This significantly reduces impact loads on all suspension components, reducing stresses, damage, and costs. Improved ride enables higher travel speeds, lowering trip times. Reduced road damage means less bumps, and more trips. Vibration levels are drastically reduced leading to healthier, happier drivers, and longer lasting vehicles, improving resale values. This is where AIR CTI really shines, with a push of a button in the cabin whilst on the move to inflate or deflate the tyres. When speed drops, and roads get rougher, lower tyre pressure will improve all operating parameters.

On Gravel Roads should I use lower Tyre Pressure?
Yes, lower tyre pressures provide 120 to 200% improvement in traction, reduced tyre damage (around 60% reduction), reduces tyre slip, reduces impact loads to your suspension and load (90% reduction), improves ride quality (heaps) improves handling, improves braking, and reduces road damage (25% minimum).

What do you mean? Extra traction at Lower Pressures?
When off highway, extra low tyre pressures will provide substantial traction benefits. Traction increases of 10 to 100% extra are obtained. The slow speeds associated eliminate heat problems. The softer the ground, the more traction available. The difference is often astounding. A standard tandem drive truck will perform better than a six wheel drive truck. Two trailers can be towed where a single trailer operator is stuck. A standard four wheel drive outperforms a modified vehicle with locking diffs.

Does low Tyre Pressure Damage the Tyres?
Tyres are designed to flex, and absorb bumps. Heat build up is what damages tyres. At reduced speeds, lower pressures provide extra flex, without heat build up. Used correctly, tyre life, including case life, is improved significantly. 18% under pressure will accelerate tyre wear by 20%. 105 psi in standard 11R x 22.5 Tyres is 20% over inflated. By matching tyre pressure to the load, tyres last longer. Even lower pressures can be used at reduced speeds for even more tyre life gains in marginal conditions.

Does extra traction break axles and damage components?
Lower pressures reduce drive train loads by at least 30%. This is because tyires flex, smoothing the power loads. Traction Off Road will never be as high as on concrete or bitumen, so loads are always lower than the everyday loads used when taking off from a traffic light.

I get Axle Tramp when Off Road. Does AIR CTI help?
Axle tramp is virtually eliminated by using lower pressures. Soft tyres absorb vibration before it can damage your axles. This smoother torque transfer is much kinder to your entire drive train and suspension, reducing maintenance costs by up to 80%.

What about Corrugations or Wash Boards?
Lower tyre pressures will actually eliminate wash boards, smoothing your road in only several passes. Experienced drivers curse those without CTI because of the damage they do to the roads.

Those External Hoses will get Ripped Off Where I go!
Very, very few 'drop' hoses are actually damaged in real life. AIR's Exclusive SNIZENTITE ® high tech plastic "drop pipes" simply fit closer and look better. AIR CTI Systems are working in Forests all day, every day, throughout Australia. Unless you are regularly wiping out fenders/mudguards/flaps, steps, fuel tanks, etc. the probability is you won't lose any drop hoses. Even on Fraser Island, which is the worst terrain I know, where buses and trucks drive in a trench with roots protruding on each side, drop hose loss is negligible.

I hear the Rotating Unions (Rotators) have a short Life Span and can't be Repaired?
Most Rotator problems are caused by outside contamination from dirt and mud. Dirt is the enemy of any seal. If the inside of the tyre is clean when fitted, seals virtually will not wear. AIR designed and manufactures our own unique rotators, specially for Australia's harsh conditions. Bearing size is huge, with triple sealing, along with carbon seals ensure long life. And they can be rebuilt. These units are designed to last up to 1,000,000 kilometers, and guaranteed for two years.

What happens if a Tyre Blows or is Staked? Is air lost from all of the Tyres?
With ordinary CTI systems, if a tyre is staked or blows, air is rapidly lost from all interconnected tyres. You must pull up immediately and turn off all tyres. There may not be a safe place to pull up, but you have no choice. With AIR CTI PROFESSIONAL systems, good tyre air loss is minimized. On drive tyres, AIR CTI invented a special automatic valve assembly (isolator) that minmises this air loss. This isolator is a unique safety feature only available from AIR CTI. High pressure Air will automatically be isolated from the tyres losing air. On trailers, we isolate the tyres from side to side. This has the added benefit of reducing air transfer when off camber and air pressures are low.

What do you mean?
When off camber with low pressures, the loads on the low side are significantly higher, which, on other's systems, can flow across to the upper tyres. This will increase the lean or tilt of your vehicle, which may be bad!!!! AIR CTI's isolator automatically minimises this air transfer.
On Side hills at lower pressure, will air transfer from the low side to the high side, and make the truck lean more and possibly roll over?
AIR's unique isolation system (AIR invented this) limits this airflow from the heavier loaded side to the lighter side automatically.

If I get a puncture, what happens?
AIR CTI's smart control system immediately senses this pressure drop and automatically reinflates your tyres. A warning message on the bright yellow display and alert beeper informs the driver.
Will blow outs or tread separation wipe out hoses and tubes?
The short answer is yes, probably, along with your fenders/guards, tail lights, and anything else close. But, CTI will eliminate most of these, because most blow outs are caused by tyre overheating or overloading that is caused by a puncture. CTI will maintain pressures in most punctures. AIR CTI will also inform the driver of the problem before disasters happen.

Explain More!
The truck's compressor and the AIR CTI system will continue to inflate a punctured tyre up to it's capacity. The display information will indicate live tyre pressure readings and any air flow alarms in progress. The Isolator provides added gauge sensitivity.

Will the tyre pressure drop so low that the beads will dislodge?
AIR CTI systems have pre set minimum pressures, and pre set maximum pressures. This limits the pressures to common practice minimums, and to tyre manufacturer's maximum recommendations for legal loads.

Will a leaking tyre or hose deflate all my tyres?
Given time, a puncture or leak can deflate those tyres connected to the CTI system. Drivers, once used to CTI, will know how their system is working, and will know when there is a problem. AIR CTI's recommendation is to turn off all wheel taps each evening when parking the truck.

How long does it take to fill the tyres?
Inflation times depend entirely on compressor volume. The bigger the compressor, the faster it fills. Same with tyre volume. Normal operation is to inflate or deflate in stages. In most cases, inflation times are only a few minutes, which occur while driving. AIR CTI uses two exhaust solenoids to reduce deflation time.

Is there a filter in the system, and what maintenance is required?
A self draining filter filters all supply air. Separate stainless mesh filters filter all tyre air, while similar filters are used before each exhaust solenoid. These provide added reliability. In most cases, cleaning is not required.

What about after sales service?
AIR CTI carefully selects each agent to ensure top quality back up. Our phones are on at least 12 hours per day.

If I have Another Question, can you answer it?
Just email us. Knowledge and information is our business. Email us at sales@aircti.com or Phone us on 61 3 5127 6128.