A common recommendation you may have heard when taking your 4WD vehicle with its new replacement bumpers off-road is that you should air down your tires and drive on lower air pressure.
Is that necessarily true?
It can be in certain situations based on what kind of off-road driving you like to do, but it might not always be necessary.
Before you start letting air out of your tires, take time to think about what it can do for you and understand that airing down brings with it advantages and disadvantages.
What Does Airing Down Tires Do?
In a nutshell, just as great replacement bumpers add greater protection to the front or rear end, airing down tires reduces tire pressure, making them more flexible.
This does two things for you when you’re off-roading:
- It gives you a wider contact patch where the tire is in contact with the ground.
- It enables the tire to flex over uneven surfaces rather than slide off them.
Both instances will give you better traction for certain off-road activities, reduce your likelihood of getting stuck, and improve your 4WD’s mountain goating ability.
Can Airing Down Damage Your Tires?
Although airing down can be a positive thing when you’re trying to gain more traction, it’s important to note that it can shorten the lifespan of your tires.
- Firstly, with a wider contact patch your treads can wear out faster than those on tires run at recommended PSI.
- Secondly, the lower you run your tire pressure, the more flex and strain it puts on the sidewall of the tire so that tearing the sidewall or even puncturing the tread becomes a greater possibility as a hard, properly-aired tire is more resilient against sharp objects on the trail just like those new replacement bumpers you just added.
- In addition, airing down can cause your tire to come off the wheel, which is an inconvenience at best and could damage wheel and tire at worst.
Fortunately, bead locks on your rims can help with that by locking the bead of the tire onto the wheel.
If you’re going to air down, it’s critical that you do it when it’s going to help you and not just because it’s a cool thing to do.
Keep all risks in mind and try to avoid damaging your tires while running on lower pressure.
Before you go too low, check your sidewall rating and make sure yours are strong enough to withstand it.
When Is Airing Down Actually Useful?
So when is airing down actually a good thing to do?
The best times to air down on the trail are any time more tire hitting the ground will give you an edge:
- Lowering your PSI by just a few points can be great for general trail riding and dirt driving, softening the tires just enough to help them grip more; however, you don’t have to air down for this type of lower-level off-roading.
- If you’re driving through mud, sand, or other soft ground situations with your off-road wonder, a softer, wider tire will keep you moving forward on top of the surface rather than digging in deeper and slowing forward momentum.
- A softer, more flexible tire will make it easier to get traction on rough trails and while rock crawling, since the tread will have a wider contact patch and be able to conform to the rocks and crevices along the way.
If you do air down, make sure you’re set up to re-inflate your tires once the surface changes and most definitely before you take your 4×4 to the streets.
Use lower air pressure on the surfaces where it’s meant to be used.
The Verdict – Should You Air Down On the Trail?
Like everything else about off-roading, it just depends on what you’re running, what you’re doing, and whether the amount of improvement to be gained is worth the risk of damage.
If you’re prepared with bead locks and tires with stronger sidewalls and you’re careful, go for it.
How much you air down will depend on your tires and many other things, so you may have to use trial and error until you get a feel for how it works.
Done the right way along with adding some great replacement bumpers, airing down can definitely give you an advantage over driving on your fully-inflated off-road tires!