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Adding air to your RV’s tires should be straight forward but when you are faced with dual tires, also known as dually tires or duallies, it can seem a little more complicated. There are a few different ways that you can go about adding air to your dual RV tires, and the best one is going to be the one that you are most comfortable with but some ways are definitely easier than others.
To inflate dually tires, access the inner valve stem (with or without an extender), attach the chuck to the valve stem and use an air compressor with a high PSI rating to fill the tires.
RV tires are expensive, and nothing puts a damper on a trip like a blowout. Properly inflating your RV’s tires is going to help extend the life of your tires and keep your trip rolling smoothly. I’ve got a couple of tips and tricks that will make the process of properly inflating your duallies easier.
Table of Contents
Adding air to the outside tire is easy – you just remove the stem cap, attach the air hose and chuck to the valve stem, fill the tire while checking the pressure, then replace the stem cap. Inflating the inside tire is when it gets fun.
One of the biggest challenges that comes with filling dually tires is accessing the inner wheel’s valve stem. If your dual rims are properly aligned then you won’t have as much trouble reaching it. If you’re like 99% of RV owners, your dual rims won’t seem to be properly aligned.
You can fix this by taking off the outside tire to reposition it so that the inner valve stem comes through the cutouts in the rim. Once your inner valve stem is at least accessible you’ll be able to fill it in the future without taking off the outside tire.
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You can either use a personal air compressor or an air pump at a gas station, truck stop, etc to fill your tires, but if you do decide to use your air compressor you have to make sure it has a high enough PSI to get the job done. Dually tires typically should be filled to 80 PSI, and not all air compressors will be able to reach that pressure.
To use your compressor you’ll want to get a pressure gauge that’s long enough to reach the valve stem, which means you’ll need about a 12-inch hose without a valve stem extension installed.
The pressure gauge will let you keep an eye on the tire’s PSI as you’re filling to make sure that it doesn’t get under- or overinflated. You can monitor the pressure by just placing the pressure gauge onto the valve stem without pumping any air into the tire.
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AstroAI Digital Tire Inflator with Pressure Gauge, 250 PSI Air Chuck and Compressor Accessories.
2; Includes an inflator, straight locking...
If a tire is under-filled it will cause more wear and tear on the tire, not to mention it can make your RV more prone to tipping over which is definitely something you do not want to deal with. If your tire is overfilled, you increase the likelihood of a blowout and you also decrease your tire’s lifespan.
In order to fill the tire, you can try using an angled inflator chuck to better reach the valve stem and you can also find them in different lengths. It may take some playing around with different chucks to find the one that works best for your RV. You can also try getting a valve stem extension with different angles like 90 degrees, 120 degrees, etc.
Once you have your air compressor hooked up, squeeze the trigger/lever on the compressor hose to pump air into the tire and release the lever to see what the tire’s current PSI is.
A valve stem extender is exactly what it sounds like – a part that you can install to extend the length of your valve stem. Most of them are made of stainless steel and they attach directly to the tire stem, and you can leave them installed so that you’re all set for next time.
Sounds great, right? No more cramped spaces, no more fumbling for the valve stem, no more hassle.
While that may sound like the best thing in the universe (especially if you’re already an hour into trying to check your dually tire pressures), most RV forums are actually pretty divided on how well they work and especially how safe they are for your RV.
Some people argue that they’re just as hard if not harder to install than just putting the chuck on the stem, and other people have had bad experiences with them leaking if left on for long periods. Still other people have reported the inside of the valve stem, which is rubber, deteriorating despite the stainless steel exterior.
On the other side of the coin many people swear by them, saying they have never had a problem and their valve stem extenders make the dually filling process so much easier.
Some newer and higher-end RVs will come with extenders already installed, which is awesome. If that’s the case then you can use them until you have to replace the tires and then look at replacing the extenders at the same time.
There are many valve extender kits that have good reviews and are recommended on the RV forums, but everyone seems to agree that you should avoid the airless stem extenders. One person reported losing two perfectly good tires in less than a year thanks to leaks from the airless extenders.
CKAuto 6 Pack 45 Degree 90 Degree 135 Degree Metal Valve Stem Extenders, Universal Valve Stem...
..This is an equalizing valve that allows air to flow freely from one tire to the other, allowing both tires to be at equal pressure. I know what you’re thinking – I just checked the tire pressures and they’re both the same. Why would I need something like this?
While the tires will be at the same pressure after you fill them, on the road is a different story. The inside tire is going to heat up more due to lower airflow and the in-board brakes, and this higher temperature is going to cause the pressure in your inside tire to rise as you travel.
As I mentioned, too-high of pressure can leave you prone to a blowout and put more wear on your tire, so the tire equalization valve seeks to remove that risk.
Products like the Crossfire Dual Tire Pressure Equalization System show you if your tires are properly inflated while allowing the higher pressure in the inside tire to equalize with the outside one. This will add to your tires’ overall life expectancy and hopefully save you money in the long run.
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Crossfire Dual Tire Pressure Equalization System, 110 PSI, one per pkg. (CF110STABT)
Did you know that a tire being 20% under inflated will cause at least a 30% loss in the life expectancy of your tire? Similarly, a tire being 20% overinflated will cause at least a 10% loss in your tire’s life expectancy while increasing the risk of a dangerous situation.
You should check your dually tire pressure before setting out on every trip, and when you fill up for gas while on your trips.
It’s especially important to check if your RV has been sitting still for a while, as dry rot can cause leaks and other issues.
Generally, your RV’s dual tires should be at 80 PSI, and to check the pressure you’ll need to make sure the tire pressure gauge is rated high enough so that you get an accurate measurement. A pressure gauge that is too low will max out without telling you if you’re actually at 80, and one that is too high may not give you an accurate reading.
But before you go and just fill your tires to 80 psi you’ll want to check the owner’s manual of you RV or the placard stating the tire pressure rating for your RVs tires. You should also check on the tire itself what the rating is.
The rating found on the sidewall of the tire will actually state “maximum load-carrying capacity and the minimum air pressure required to carry this load”. This means it’s a good idea to know what your RV actually weighs for each axle when you are fully loaded for a trip, including all passengers.
Tire pressure should also be checked when cold. This is because when you start driving your tires warm up, increasing the air pressure in your tire. Any manufacturer rating from both the tire and RV will be for a cold tire.
A tire pressure monitoring system is exactly what it sounds like – a way to monitor the air pressure of your tires in real time. This is done through the electronic system that sends periodic reports to the main console and will also alert you of any potential issues.
A sensor is mounted in each wheel or as part of your anti-lock braking system (depending on the model), and these sensors are what monitors your tire pressure,
These systems are fairly pricey up front, but they will save you a lot of money and time on the back end by allowing you to keep your tires inflated at the ideal pressure and therefore reducing the wear and tear on them.
Some monitoring systems will only track pressure while others will also give you information about temperature.
The EEZTire-TPMS6 system will give you real-time updates about both while also providing audio and visual alerts to any problems, and it’s one of the highest-reviewed monitoring systems on the market.
EEZ RV Products EEZTire-TPMS6ATC Real Time/24x7 Tire Pressure Monitoring System - Color Monitor + 6...
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The Fix It Yourself RV Maintenance Course is the perfect way to learn how to do the most common repairs and maintenance on your RV. A Certified RV Technician wrote and filmed the course so you know the information is actually correct.
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Closing ThoughtsNow you know how to inflate dual RV tires and why it’s important, and hopefully, you’ll be more confident the next time you get ready for a trip. Just remember to use a compressor with a high enough PSI, choose your valve stem extender wisely, and don’t be afraid to take the outside tire off in order to get the inner valve stem positioned where it’s supposed to be.
| Preview | Product | |
|---|---|---|
EEZ RV Products EEZTire-TPMS6ATC Real Time/24x7 Tire Pressure Monitoring System - Color Monitor +. .. | Check Latest Deals | |
| Crossfire Dual Tire Pressure Equalization System, 110 PSI, one per pkg. (CF110STABT) | Check Latest Deals | |
CKAuto 6 Pack 45 Degree 90 Degree 135 Degree Metal Valve Stem Extenders, Universal Valve Stem. .. | Check Latest Deals | |
| AstroAI Digital Tire Inflator with Pressure Gauge, 250 PSI Air Chuck and Compressor Accessories... | Check Latest Deals | |
GSPSCN Silver Dual Cylinder 12V Air Compressor Pump for Car, Heavy Duty Portable Tire Inflator. .. | Check Latest Deals |
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We’ve changed the way we add air to our RV’s tires. Before, we used our diesel pusher’s onboard air compressor, but this new way applies to any type of RV, so this tip isn’t just for owners of large motorhomes.
If you’ve seen our previous videos about adding air to high-pressure tires on diesel RVs, you know that using the built-in compressor might not be as simple as it sounds.
Besides the problem of the pressure cycling up and then down below our required tire pressures as part of its normal operation, we also try to avoid idling our engine more than absolutely necessary. We hate being an annoying neighbor by polluting a campground with diesel exhaust and noise just because our tires happen to need air. Our new solution not only makes the job easier, but also makes us a better neighbor.
If you’ve seen very many of our videos, you know that we’re all about finding cost-saving ways to solve RV issues, but sometimes a top-of-the-line solution is the best solution, and you get what you pay for.
We discovered Viair, a manufacturer of ruggedized portable compressors, designed to handle more demanding situations, like filling large off-road vehicle tires. We like the fact that they make a model specifically designed for RVers (we use the Viair 400P-RV), which has stellar reviews on Amazon, so of course that’s the one we ordered.
For full-timers, space is limited, so every piece of equipment has to provide value.
We made room on our RV for this unit, and we’re sharing it because we think it’s such a worthwhile addition to our rig.
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Air CompressorTiresViairPLEASE NOTE: We're handy RVers, not professional technicians.
We're happy with the techniques and products we use, but be sure to confirm that all methods and materials you use are compatible with your equipment and abilities. Regardless of what we recommend, consult a professional if you're unsure about working on your RV. Any task you perform or product you purchase based on any information we provide is strictly at your own risk.
We participate in the Amazon affiliate program, which provides a means for us to earn a small commission by linking to products there. But our opinions are our own and we only link to products we can recommend to friends with complete confidence. And using our links won't cost you an extra penny!
Optimum tire pressure is a guarantee of the safety of car passengers, as well as a guarantee of tire durability.
The car must be “cold”, that is, before the measurement, the car’s mileage must be less than a couple of hours, the vehicle must travel no more than 2 km.
When you need to measure the pressure urgently, subtract 0.3 bar from the measurement. The operation should be carried out before every big trip and more often than once every 30 days. It is important not to forget about the spare wheels: they also need to check the pressure level. The optimal level varies, so it’s worth asking the manufacturer for the exact figure, and it wouldn’t hurt to find the instructions for the car and look there. The value can be marked on the body compartment, gas tank and side pillar.
It all depends on the weather and operating conditions. The nominal mark varies, for example, on how warm or cold it is outside the car. Drops in winter have a strong effect, so experts recommend adding 0.2 bar to the measurement result to objectively determine the pressure level.
If the pressure level on the front axle is less than the nominal one, then this will change the handling: the wheels will turn poorly.
Incorrect pressure in the rear will cause the car, on the contrary, to move too sharply. Slip on wet pavement appears due to a decrease of 0.5 bar, since the contact of the tire with the road becomes less. A level of 2 atmospheres will lead to full contact. The lower the contact, the greater the risk. Therefore, the pressure affects the quality of the ride.
In addition, the lower the level of inflation of the wheels, the greater the consumption of gasoline, and this promises financial losses. Too much pressure increases tire wear. Therefore, do not underestimate the importance of maintaining the pressure level set by the manufacturer. This can lead to a car accident.
The ability of a tire to withstand loads is directly related to pressure. If the pressure is low, do not overload the car. When determining the optimal level, you do not need to focus solely on the tire load index.
Raising the level is permissible if it is necessary to increase the carrying capacity of the car.
But for most cars, this is dangerous by the rapid destruction of tires. For trucks, special tires are sold that provide an additional degree of protection. They have a special designation: XL, Reinforced or "C".
The ability to accelerate the car depends on the inflation of the tires. To increase the speed, the pressure is increased. The ZR index on the tire indicates that with such a tire you can reach speeds of up to 245 km per hour. But we advise you to contact the manufacturer for details and clarify this indicator.
A pressure of 3.2 atmospheres is optimal for tires with a T marker. An increase of this figure by 0.3 atmospheres is suitable for tires marked H, W, V, Y, ZR. Exceeding these figures is dangerous in many ways. Adequate pressure ensures proper weight distribution and longer life.
When the nominal pressure in the tires is lowered, the wear resistance becomes less because heat begins to be generated. Because of this, overheating and destruction occurs.
Pressure below normal leads to a deterioration in indicators such as the ability to maneuver and elasticity.
Note that tire pressure is an important property that must be monitored. Failure to pay attention to a detail that is so important for safety can lead to damage to the vehicle and to an accident. It should become a good habit for the driver to maintain the correct level.
Do not try to determine the pressure yourself. Use a manometer. This device will accurately measure the indicator. For a novice car enthusiast, it is not easy to realize the level of pressure by internal sensations, it is important to contact the salons and ask to pump up the tires. A decrease in temperature by 8 degrees entails a decrease in pressure by 0.1 atmospheres.
Don't underestimate the importance of tire condition. The life of people sometimes depends on the strength and wear resistance of wheels. In this regard, it is necessary to properly care for the tires.
As already noted, incorrect pressure can cause poor handling and tire damage. Let us remind you once again of the importance of checking the pressure on a car that has traveled no more than 2 km on the day of the control.
Is there a valve cap? If not, then the nipple will be prone to contamination. Check tires for cuts, cracks, holes or bulges. All this speaks of dilapidation. There should be no foreign objects, including wires and glass. Remember that a tire with such damage is not suitable for use. Do not bring to the destruction of the tire on the go.
Wear leads to breaks. There is a fear of losing control when driving through puddles. Keep track of the remaining tread height. According to the traffic rules, it is forbidden to use a car whose residual height of the pattern is less than 1.
6 mm (for cars), 1 mm (for trucks) and 0.8 mm (for motorcycles).
For winter tires, the minimum residual tread depth is 3-4 mm. When the tire is used for too long, there is a danger that the handling on the water will be worse.
For motorists with an aggressive style, tires deteriorate much faster. It is also worth taking into account the climate and features of the road surface.
Proper inflation of the wheels and constant maintenance of the optimal level is the key to safe movement. Do not be too lazy to look in the instructions for what pressure should be in the tires.
If in doubt, call the manufacturers or go to a car dealership where professionals will adjust the pressure.
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Inflating a tire in the city is not a problem. There will always be a thrifty car enthusiast nearby who will lend a compressor. In extreme cases, you can drive to the nearest auto parts store and buy this useful device. But if the need to pump up the wheel caught on a long journey, on a deserted track, you will have to use your ingenuity.
A very banal way is to turn to professionals, that is, truck drivers. The fact is that any truck with pneumatic brakes can supply dried and purified air with high pressure through a hose that a thrifty truck driver always has with him.
Many gas stations now have tire inflation points, and perhaps the easiest way is to hitch a wheel to it and then return to your car in the same way.
If all of the above did not work, then read about the tricks that we personally tested for effectiveness:
Attaching a can (any) to the nipple is not so difficult. The pressure inside the cylinder is 1.8-2.8 bar. It is important that the contents do not dissolve the rubber and do not harden, such as building foam.
Here, of course, compressed air canisters are good for blowing, for example, office equipment. But the inner volume of a wheel of a small class car is about 20-25 liters. For pumping, you will need several boxes of cans. Unacceptable!
It is possible to connect the tire valve to the brake master cylinder connection after draining the reservoir. After that, we begin to press the brake pedal in the same way as is usually done when bleeding the brakes when replacing the brake fluid. To inflate the wheel, it will take a gigantic number of clicks.
Unacceptable!
Connect the hose to the air path after the turbocharger. The boost pressure in the line between the compressor and the intake valves of conventional (non-sport) engines is not enough to inflate the wheel. No matter how you gasp - unacceptable!
Advanced car enthusiasts know the method of transferring the bead ring over the rim hump using fuel vapor explosion. The Internet is full of videos on this topic.
It is usually advised to unscrew the spool from the valve. I wonder what will happen if this is not done? We need to keep up the pressure. We conducted an experiment and got an unsatisfactory result. With this method, it is possible to provide a very small pressure in the wheel - about 0.2 bar. The method really allows you to brilliantly cope with the task of transferring the sidewall through the hump, but it is not suitable for pumping!
And this is perhaps the most unusual way to inflate a tire.
After conducting an experiment with a large 6-kilogram fire extinguisher, it was possible to raise the pressure by a completely ridiculous amount of a couple of tenths of a bar. And this despite the inverted spool. Everything around was covered with a rather nasty powder. Unacceptable!
The average car owner usually has a powder-type fire extinguisher in the trunk. A powder fire extinguisher of a rather large volume worked very badly. It was not possible to pump up the wheel.
The average car owner usually has a powder-type fire extinguisher in the trunk. A powder fire extinguisher of a rather large volume worked very badly. It was not possible to pump up the wheel.
If you can attach a hose to the exhaust pipe, then you can inflate the wheel in this way. The engine is able to provide a pressure of two or more bars with a sealed exhaust system and if you “give it a gas”. The method is acceptable, but only as a last resort.
The fact is that with this method, the catalytic converter, and even the corrugation of the exhaust system, may suffer.
The most difficult thing is to achieve a tight joint between a thin hose and an exhaust pipe. A variety of caps from bottles, washers, water squeegees can go into business. What will be at hand. Electrical tape will help seal the connection.
The most difficult thing is to achieve tightness of the joint between the thin hose and the exhaust pipe. A variety of caps from bottles, washers, water squeegees can go into business. What will be at hand. Electrical tape will help seal the connection.
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If you want to pump up a wheel, jack up the car! Debunking the Myth
Using a hose, you can transfer part of the air from other wheels to the one we need to inflate. The method is complicated, because the valve mechanism will interfere with such a procedure.
