Air suspension is very reliable when it is installed properly, but air has one annoying habit - it likes to escape.

Most leaks are small. Common causes include:

• Damaged airline.
• Cheaply made, poor-quality fittings, air bags, valves, or other components.
• Poorly cut pipe.
• Old components.
• Threaded fittings that need cleaning and resealing.

The important thing is not to panic and not to make the problem worse.

One of the most common mistakes is also one of the most tempting: do not simply tighten the union.

It feels logical. If air is leaking from a fitting, surely tightening it a little more will help? It is a tapered thread on most fittings, so that will work, won't it?

In reality, it rarely does. More often, it damages the fitting, damages the thread, or both. At AirRide, the fittings we install are normally sealed using liquid PTFE thread seal. When installed correctly, these unions are extremely reliable. However, no air system is completely immune from leaks forever. If a leak does appear, the right repair is not brute force. The right repair is to remove, clean, inspect, reseal, and reassemble.

Why Tightening the Fitting Is Usually the Wrong Answer

Most threaded air suspension fittings are not designed to be endlessly tightened.

If a fitting is leaking from the thread, there is usually a reason. It may have disturbed sealant, contamination in the thread, a damaged fitting, an old seal, or a thread that needs cleaning. Simply turning the fitting tighter often does not fix the underlying problem. It will regularly make the situation worse.

What it can do is:

• Round off or damage the fitting.
• Crack or distort the fitting body.
• Damage the tapered thread.
• Tear material out of the component the fitting screws into.
• Turn a simple resealing job into a much more expensive repair.

A damaged fitting is normally easy enough to replace. A damaged thread in a tank, suspension bracket, valve block, or strut is a different matter. That can be awkward, time-consuming, and expensive to repair. It may require replacement of the component.

This article was prompted by a real example. A customer recently had a small leak. Rather than removing and resealing the fitting, he tried tightening it. The result was a damaged fitting and, more seriously, a torn-out thread. What should have been a simple cleaning and resealing job became a much bigger problem.

Most Air Suspension Threads Are Tapered

Many of the fittings used in air suspension, and almost all used on our AirRide suspension systems, are either 1/8 NPT or 1/4 NPT. NPT is a tapered thread. That means the thread tightens progressively as it screws in. It does not work like a normal parallel bolt thread where you simply tighten it against a face.

Because the thread is tapered, over-tightening can force the fitting too far into the component. This can damage the female thread, split softer materials, or tear the thread out completely.

This is why technique matters.

The Correct Way to Repair a Leaking Threaded Fitting

If you suspect a leak from a threaded fitting, the correct repair method is straightforward.

1. Depressurise the System Safely

Before working on any air suspension component, make sure the system is safely depressurised. Do not remove fittings from a pressurised system. Air pressure can eject fittings, airline, or debris with force.

2. Remove the Fitting

Remove the leaking fitting fully. Do not just move it a quarter turn and hope for the best.

Once the fitting is out, you can properly inspect it and the thread it screws into.

3. Clean the Fitting

Remove old thread sealant, dirt, corrosion, and any loose material from the fitting. You can do this with a wire brush and, where suitable, some solvent. If you have one, an NPT die can also assist.

Check carefully for damage. Look for:

• Rounded spanner flats.
• Damaged or flattened threads.
• Cracks in the fitting body.
• Distortion from over-tightening.
• Old hardened sealant stuck in the thread.

If the fitting looks damaged, replace it. Fittings are relatively inexpensive. Damaging the part it screws into is not.

4. Clean the Female Thread

The female thread also needs to be cleaned. This is the part in the tank, bracket, strut, valve block, or other component.

Old sealant can sit inside the thread and prevent the fitting from seating properly. Dirt or damaged material can do the same. A suitable NPT tap can be used carefully to clean the thread. These taps are readily available online, and even a cheap tap can often clean out a thread well enough to save it.

The aim is not to aggressively cut a new oversized thread. The aim is to clean the existing one and remove debris, sealant, and minor damage.

Remove all swarf and loose material - ideally with a vacuum, not an airline, which can blow debris deeper into the system. You may need to remove the tank or other part you are repairing so it can be cleaned properly.

5. Inspect Both Parts

Once everything is clean, inspect the fitting and the female thread. Ask yourself whether the fitting will still screw in dry and tighten smoothly by hand.

If the thread is badly damaged, stop. Forcing another fitting into a damaged thread may make the repair harder.

6. Identify the Correct Replacement Fitting

If the fitting needs replacing, make sure you order the right one.

You will need to know:

• Is it a straight fitting or a 90-degree elbow?
• Is the thread 1/8 NPT, 1/4 NPT, or something else?
• What size airline does it accept?
• Is the airline 1/4 inch, 3/8 inch, 1/2 inch, or metric?
• Is it push-to-connect, compression, barbed, or another fitting type?

At AirRide, we only use push-to-connect, or PTC, type fittings, which seal on the outside of the airline. Some other manufacturers use barbed fittings. The most common airline size in many air suspension systems is 1/4 inch, but you should always check. Guessing can easily lead to ordering the wrong part.

7. Apply Liquid PTFE Thread Seal

Before reinstalling the fitting, coat the thread with liquid PTFE thread seal. We use liquid PTFE because it works as both a lubricant and a sealant. It helps the fitting screw in smoothly and helps create an airtight joint.

It is also quite forgiving of slight damage, although we would always recommend changing a damaged fitting as the preferred solution. We cannot guarantee that sealant will seal a damaged thread.

Even if the fitting already has manufacturer-applied sealant on it, we still recommend liquid PTFE. The pre-applied sealant is not always enough on a new fitting, and this is especially true if the fitting has been removed and refitted.

Do not apply excessive sealant inside the fitting where it could enter the air system. Apply it to the thread in a sensible, controlled way.

Do not, under any circumstances, use plumber's PTFE tape. In our experience, it does not seal as reliably, is not as reliable over time, and bits can break off and enter the system. We do not use PTFE tape on any system we install. We recommend use of our sealant available HERE. We supply it free with all complete systems we sell.

8. Reassemble Carefully

Refit the union carefully.

Start it by hand to make sure it is not cross-threaded. If it does not start cleanly, stop and inspect it again. Tighten it enough to seal, but do not force it. With tapered threads, tighter is not always better. The fitting should be secure, correctly positioned, and sealed, not driven in until something gives way.

9. Allow Time for the Sealant to Cure

If possible, leave the joint for at least an hour before pressurising the system.

If you have plenty of time, leave it for 24 hours. This gives the sealant more time to cure and gives the best chance of a reliable repair. In the real world, repairs sometimes need to be done more quickly, and this is acceptable, but where time allows, a better seal will be achieved.

Our sealant cures in the absence of air - in other words, inside the threads. The outside air-exposed part may remain sticky. The sealant is not an adhesive, and it will still allow the components to be removed in the future.

10. Test the Repair

Once reassembled and cured, pressurise the system and test for leaks.

A soapy water test is still one of the simplest and most useful methods. Spray the area and watch carefully for bubbles.

If bubbles appear, do not simply tighten the fitting again. Depressurise the system, remove the fitting, and inspect it or replace it.

A Small Leak Is Usually a Small Job - Until It Is Made Worse

A small air leak is annoying, but it is usually not a disaster.

The problem comes when a small leak is attacked with a spanner instead of repaired properly. A damaged fitting can be replaced. A torn thread in a tank, bracket, strut, or valve block is much more serious.

So the rule is simple:

If a threaded fitting leaks, do not just tighten it. Remove it, clean it, inspect it, reseal it with liquid PTFE, refit it carefully, allow it to cure if possible, and then test it.

That approach takes a little longer, but it can save a lot of money, damage, and frustration.

If you own a Fiat Ducato, Peugeot Boxer, Citroen Relay or Citroen Jumper based van, camper or motorhome, there is a good chance that air suspension will make a very worthwhile difference to the way it drives, sits and copes with load. These vehicles have been one of the most important bases for European motorhomes for many years, and for AirRide they remain one of the biggest parts of our van and motorhome air suspension business.

In fact, our rear load support kits for the Ducato platform are our single most popular load support kits, accounting for around a third of all the load support kits we sell. For much of the last twenty years, Ducato based motorhomes made up the majority of the market. That is changing somewhat now as more manufacturers move towards Ford based vehicles, but the Ducato, Boxer, Relay and Jumper platform is still one of the most common and most important vehicle families on the road.

With the weather improving and more owners starting to think about weekends away, holidays, touring and getting their vehicle ready for the season ahead, now is a very good time to upgrade. We currently have good stock of popular Ducato air suspension kits and can also advise on front struts and AL-KO applications.

Why Fiat Ducato motorhomes and vans so often benefit from air suspension

The Fiat Ducato and its sister vehicles are used for panel vans, camper conversions, coach built motorhomes, A-class motorhomes, minibuses and commercial vehicles. That flexibility is one of their strengths, but it also means many of them work hard and carry a lot of weight. Water tanks, passengers, tool kits, mobility equipment, bikes, tow bars, scooter racks, luggage and general conversion weight can all take their toll on the rear suspension.

Many motorhomes are effectively running too close to the bump stops for comfort. When that happens, you lose suspension movement, ride quality gets harsher, the rear end can sag, the vehicle can feel less settled and the whole thing becomes more susceptible to wallowing, crosswinds and the buffeting effect of large passing vehicles.

A good rear air suspension kit for a Fiat Ducato, Peugeot Boxer, Citroen Relay or Jumper can help recover lost suspension motion, improve ride quality, improve stability, reduce sagging and help the vehicle sit and drive more as it should.

The toughest Ducato rear load support kit we know of

We believe the Boss bagged rear load support kit we supply for lifted Fiat Ducato, Peugeot Boxer, Citroen Relay and Jumper applications is the heaviest duty kit on the market that we know of.

• Heaviest duty bags we know of
• Heaviest duty brackets we have seen
• Proper high quality fittings
• Extremely simple bolt-on fitting
• Designed specifically for hard-working vans, campers and motorhomes

That matters because all air suspension kits are not the same. The internet is full of low-priced air bag kits, unbranded bags, weak brackets and poor fittings. In this market, cheap often means compromised. Suspension parts are carrying real load on heavy vehicles, so bracket design, steel thickness, bag quality and fittings quality all matter a great deal.

Boss Extreme air bags - serious specification for serious vehicles

This rear kit uses two Boss Extreme double convoluted air bags. These are rated in use at 1136 Kg per side (max 2000 Kg per side) and have been government approved tested to over 750 psi. They can be used up to 400 psi and are recommended at a maximum of 160 psi in service. Most owners will never need anything like those figures in normal use, but that huge reserve of capacity tells you a lot about the specification of the bags.

In normal motorhome use, pressures are often far lower than the bag is capable of, which is exactly how we like it. It means the kit is working well within a robust design range rather than near its limit.

Heavy duty 6 mm brackets and proper support

The brackets are just as important as the bags. Our Ducato based rear kits use proper heavy duty steel brackets made from 6 mm steel with real braces and supports where required. A good air bag fitted to a poor bracket is still a poor kit. Brackets must be designed to carry the load safely and properly without slipping, bending or creating issues elsewhere.

We do not use pressed single-piece brackets of the type known to cause chassis damage on this application (due to not spreading the heavy load over a large enough area). Our brackets are properly designed for the job, built for strength and support, and this kit is made in Norwich.

Over the years we have replaced or advised against a lot of poor quality kits. That is one of the big differences between dealing with an air suspension specialist and buying blind from a generic seller. We do not just move boxes. We have years of practical experience in supplying, fitting and supporting air suspension systems.

Easy to fit - no drilling, no nonsense

One of the biggest selling points of this Fiat Ducato rear air suspension kit is that it is also one of the easiest to fit. On the correct vehicles, it replaces the bump stops with heavy duty brackets and bags, and the installation is extremely straightforward. Remove the bump stop and fasten the new assembly in place. That is it.

No unnecessary complexity, no elaborate fabrication and no drilling for the basic mechanical installation. That makes it attractive for capable DIY owners, local garages and professional installers alike.

What are the real world benefits?

A properly chosen and properly fitted air suspension assistance kit for a Fiat Ducato, Peugeot Boxer, Citroen Relay or Jumper can help with a wide range of common complaints.

• Improves ride quality
• Helps recover lost suspension movement
• Lifts a sagging rear end
• Improves stability and handling
• Reduces wallowing
• Helps with crosswinds and passing lorries
• Improves behaviour with bike racks, carriers and towing
• Helps reduce grounding on ramps, ferries and awkward driveways
• Can make the vehicle feel more controlled and more comfortable

For many motorhome owners, the biggest difference is that the vehicle simply feels more composed and more pleasant to drive.

Important - not every Ducato based vehicle takes the same rear kit

This is where real experience matters. Many sellers advertise one kit as fitting everything from the mid-1990s onward. In our experience, it is not always that simple.

Newer Fiat Ducato, Peugeot Boxer, Citroen Relay and Jumper models, particularly post-2020 vehicles, often need a different lower profile rear kit because there is less room between the chassis and leaf spring near the bump stop area. Some earlier vehicles may also need the lower kit if there is limited space, especially on heavier conversions.

We have seen examples where a standard style kit can be physically installed but the bags end up too compressed to work properly. In that situation, ride quality can actually get worse rather than better. That is why choosing the correct kit matters.

As a general guide, if there is less than 200 mm of room between the chassis and the leaf spring at the intended ride height, you may need the lower or later type of kit. If you are unsure, contact us and we will help you identify the correct option.

We are also often asked about later vehicles with an electronic handbrake and vehicles fitted with composite rear leaf springs. This kit can be fitted to both, and always has been able to. If you are unsure about your exact suspension specification, just contact us and we will be happy to advise.

We also offer Fiat Ducato front struts

AirRide also offers front struts for all post-2006 Fiat Ducato based vehicles and for some post-2000 vehicles as well. These front strut solutions are ideal for owners wanting more control over front ride height, better balance, improved front end behaviour or a more complete air suspension solution.

If your vehicle is heavier than average, is an A-class motorhome, or you want a more advanced setup than rear assistance alone, please ask us about front air struts.

AL-KO chassis Ducato, Boxer, Relay and Jumper kits also available

Many motorhomes based on the Fiat Ducato, Peugeot Boxer, Citroen Relay and Jumper platform use AL-KO chassis rather than the standard rear suspension arrangement. We also offer kits for AL-KO based vehicles, but the fitment details can vary and some applications need additional advice before ordering.

If you have an AL-KO based motorhome, please contact us for more details and we will point you in the right direction.

Why buy from AirRide?

We are air suspension specialists with one of the largest product ranges in the market and more experience in this field than any company we know of. We deal with real installations, real customer problems and real vehicle differences. That practical knowledge makes a big difference when you are trying to choose the correct kit for a specific van or motorhome.

We do not compromise safety or specification just to get the price down. Even our basic kits are chosen and supplied with reliability, fitment and proper support in mind.

Get your Ducato air suspension sorted before the season gets busy

If your Fiat Ducato, Peugeot Boxer, Citroen Relay or Citroen Jumper is sitting low, riding poorly, grounding out, feeling unstable or simply not performing as it should, now is a very good time to sort it out. We currently have good stock of popular Ducato rear load support kits and can also advise on later vehicles, front struts and AL-KO applications.

Call AirRide on 0800 772 0315 or email enquiries@airride.uk for advice on the correct kit for your vehicle.

Whether you know it as a Ducato, Boxer, Relay or Jumper, we can help you choose a proper heavy duty air suspension solution that is built to do the job properly.

After a very mild December, winter has arrived. Us East Anglians mostly see snow on TV but at the moment we ourselves are scraping ice off windscreens and driving on snowy roads. As a result, we've had enquiries from people concerned about their air suspension so here are a few tips for the current weather conditions...

Cold weather can present challenges in cold weather, especially for retrofit or aftermarket systems. These challenges primarily arise from two factors: moisture freezing inside the system and reduced elasticity of rubber components in low temperatures. Proper maintenance and preparation can help you ensure your air suspension system functions reliably, even in the harshest winter conditions.

Key Challenges and Solutions

1. Moisture Freezing Inside the System

Condensation is a natural by-product of air compression, but in cold weather, any moisture inside your system can freeze, leading to blockages in airlines, valves, and fittings.

How to Prevent Freezing Issues:

• • Drain the Air Tank Regularly: Water accumulates in the tank over time. Draining it monthly - or more often in humid climates - prevents water buildup that could freeze.
  • Add Airbrake Antifreeze: Specifically designed for pneumatic systems, airbrake antifreeze can be added to the airlines to prevent freezing in extreme conditions. This is especially important if your vehicle is used in subzero climates.
  • Install a Water Trap, Dryer, or Cooling Coil: Water traps capture condensation before it enters the airlines, while air dryers actively remove moisture. Cooling coils can also help by condensing and collecting water vapor before it freezes. These are effective upgrades to ensure a dry air supply year-round.

2. Reduced Elasticity of Rubber Components

At low temperatures, rubber becomes less elastic, which can impact the flexibility and performance of air bags.

How to Maintain Rubber Components:

• Use Branded, Subzero-Rated Air Bags: Most high-quality branded air bags are rated for temperatures between -30° C and 70° C, making them suitable for year-round use. Choose air bags with these ratings to ensure durability in freezing conditions.
• Inspect Regularly for Damage: Check for cracks, hardening, or brittleness in the air bags and hoses. Catching issues early can save you from unexpected failures in extreme weather.

Air suspension systems are used all over the world. Vehicles like Range Rovers and Bentleys, which often come with factory-installed air suspension, are designed to operate in freezing conditions. Additionally, many buses, lorries, motorhomes, and 4x4s use air suspension in cold environments, such as the Baltic States, Nordic countries, and ski resorts.

The key to reliability in these conditions is proper moisture control and quality components. With regular maintenance, freezing issues can be entirely avoided - even in temperatures as low as -30° C.