When you buy brand new tires with your hard-earned money, you damn sure expect them to at least hold air pressure.
But what if that’s not the case? What if your brand new tire is somehow still losing air pressure?
Well, I’ve seen this happen a few times at my shop, and recently, even a friend of mine had the misfortune of having to deal with this. It’s rare but does happen from time to time.
Fortunately, there are only a handful of ways that a tire can lose air pressure and if you’re familiar with them, then finding air leaks is quick and easy. Better yet, since your new tire is losing air pressure, you can pretty much rule out punctures (probably).
In this article, we’ll cover all about tire leaks, how to find them, how to fix them yourself, and how much does it cost to fix them. Let’s get you back on the road.
Four Possible Reasons for a Brand New Tire Losing Air Pressure
First off, it is normal for brand new tires to extremely slowly lose air pressure at the rate of 1-3 PSI a month. It is also normal for brand new tires to lose 1 PSI for every 10 °F drop in temperature due to air molecules inside the tire contacting and taking up less space.
With that out of the way, if you’ve stumbled upon this article, then I assume that your new tire is losing a whole bunch of air pressure and not a measly and barely measurable 1 PSI, so here are the only four possible reasons why your brand new tire is losing air pressure.
1. Bad Seal on The Bead
The tire’s bead is the edge that sits on the wheel. It’s absolutely critical for the bead to seal perfectly against the wheel’s bead seat or else the tire will leak air and go flat.
Now, there are a bunch of reasons why the tire’s bead would not make a perfect seal against the bead seat.
The most common one is corrosion. Have you seen how badly bubbled up and corroded aluminum wheels are on some cars? Well, the same corrosion can happen at the bead seat, where the tire’s bead is supposed to seal against. Cheap chrome wheels are notorious for that, as their poor quality chrome coating flakes off and causes leaks around the bead.
Another quite common reason is improper tire mounting procedure by the mechanic/technician. It’s no secret that a lot of techs at tire shops are pretty clueless and/or don’t get paid enough to do the job properly. If the technician didn’t inspect the condition of the bead seat, didn’t clean it, and simply plopped the tire on a dirty or corroded rim, then no wonder that the brand new tire is leaking air. There have even been cases where the plastic label inside the tire got between the bead and the bead seat.
2. Leaky Valve Stem or Valve Stem Core
The second most common reason why some new tires lose air pressure is a bad valve stem.
The valve stem is supposed to be replaced every time you replace the tire. If your old tire was leaking air on the same rim as the new tire and the valve stem was not replaced, then it could be because the valve stem was and still is leaking air.
Valve stems usually leak through the valve core, which is found under the dust cap. In rarer cases, they can also leak through their rubber base if it’s not making an airtight seal against the wheel.
Valve stems cost next to nothing, therefore it’s always a good idea to replace them every time you replace your tires. Also, keep in mind that the surface on the wheel that contacts the base of the valve stem needs to be free of dirt and corrosion, otherwise it could leak air.
3. Bent or Damaged Wheel
Everybody hates potholes. Not only do they shake the hell out of your car’s suspension, but they are notorious for bending, warping, and cracking wheels.
Wheels need to be perfectly round in order for the tire’s bead to make an airtight seal. If there’s any warping or other damage from hitting potholes, then the tire might not seal properly against the wheel and leak air.
In some cases, it can be pretty difficult to tell if the wheel is bent or cracked. If the tire tech mounted your brand new tires on a warped wheel, then the new tire will surely leak air.
4. Sneaky Puncture? Defective Tire?
In 99.99% of cases, the reason why a new tire is losing air pressure is either a bent wheel, bad valve stem, or a bad seal on the bead.
However, if none of these are the reason why your new tire is leaking, then you might have fallen victim to an unfortunate nail that punctured your new tire right after the tire was mounted.
Yes, it sounds silly, but these things happen. And if there really are no punctures, and everything else is fine, you could have a defective tire. Luckily, the warranty will cover that.
How to Find a Tire Leak
Now that you know exactly where to look for a tire leak, it’s time to find it, and there is no better way than the trusty soapy water spray.
Spray Soapy Water Onto the Wheel
You can also use a leak detector spray if you want to, but you can save yourself some money by mixing up 80% water and 20% dish soap in a spray bottle. Keep in mind that some leaks can take a few minutes to bubble and show up, so be patient. Let the soapy water stay on for 5 minutes if you can.
Spray the soapy water all around the rim on both sides, where the tire meets with the wheel. By doing this you will check for both warping and bad seal on the bead.
After that, unscrew the dust cap from the valve stem and spray soapy water on the valve core and the rubber base of the valve stem.
Lastly, if you haven’t found the leak yet, then coat the whole tire and the inside of the wheel with soapy water. Don’t leave any spots dry.
Put The Wheel Into Water
Another great way to check for tire leaks is to submerge the whole wheel into water. Hold the wheel still and watch for air bubbles accumulating or floating to the surface. It might take a few minutes to see bubbling.
How to Fix a Brand New Tire That’s Losing Air Pressure
Fixing tire punctures is easy in most cases, but if your brand new tire is losing air pressure, then it’s almost certainly not because of a puncture.
In this case, only the valve core can be replaced without having to break the bead and then mount the tire again. Everything else requires breaking the bead and probably even removing the tire from the wheel. Needless to say, everything apart from valve core replacement is better left to a professional with a tire machine.
Replace the Leaky Valve Core
The valve stem core is a small metal piece that treads inside the valve core. Valve stem cores cost cents and are extremely easy to replace, but you do need a valve core removal tool to replace them. Luckily, the tool is cheap too and won’t cost you more than a few dollars.
Replacing them is super easy. Just use the valve core removal tool to unscrew the old valve core and screw in the new one. Easy as that.
Break The Tire Bead If Necessary
Since everything else apart from valve stem core replacement needs for the tire to be halfway off the wheel, you will have to break the bead of the tire. Again, this is better left to a professional, as doing so yourself without a tire machine will very likely scratch your wheels and might even damage your new tires.
There are two ways to break the bead – using a jack and driving over the tire. Neither of those is good for the tire or the wheel, but can be done in a pinch. Here’s a great video detailing the process.
My preferred way is placing a board on the tire and driving over it just enough to break the bead. Drive over it too much and you will squish the metal carcass of your new tire and damage it.
Replace the Valve Stem
If the valve stem is leaking air at its base, then you will have to break the bead and replace it from the inside of the wheel.
Once the tire is dismounted, replacing the valve stem is simple. Cut off the valve stem with angle cutters, push the part that’s left out, and push in the new valve core.
Clean The Bead and The Bead Seat
If the new tire is leaking because there’s dirt or corrosion between the bead and the bead seat, then you’ll have to break the bead or dismount the tire entirely to get access.
It’s best to completely remove the tire from the wheel to inspect the bead seat surface for dirt and corrosion and the bead itself for cuts and tears.
Once you’ve done that, clean the bead seat with a wire brush. Make sure that it’s nice and smooth. If there’s bad corrosion there, it might be a good idea to remove it with sandpaper and spray paint over it for protection.
Fix or Replace the Warped Wheel
Wheel damage is not something that you can reliably fix yourself. Aluminum wheels can be pretty brittle and straightening them out by yourself will most often than not leave you with an even more damaged wheel.
Consider replacing the damaged wheel or taking it to a professional.
How Much Does It Cost to Fix a New Tire That’s Leaking Air?
If you would rather pay a professional to fix your tire problem, then you might be interested in knowing how much it would cost. Here are the rough estimations for replacing the valve stem, bead leak repair, and wheel straightening,
Valve Stem Replacement Cost
Valve stems are dirt cheap at $4 for a pack of two. Now, when it comes to labor you can expect to pay $10 to $30 if your car does not have tire pressure sensors. If it does, then you can expect to pay around $60 to $130 since the process is much more difficult.
Bead Leak Repair Cost
If your brand new tire is losing air pressure at the bead due to chrome peeling off, rust, or dirt, then you can expect to pay $15 to $20. If you bought the new tire from the same tire shop, then bead leak repair will be done free of charge.
Wheel Straightening Cost
Straightening a warped wheel can cost quite a bit of money. In most cases, tire shops charge $120 to $150 per wheel. If the wheel is cracked or badly damaged in any other way, it might require welding, which could set you back by $250 to $300.
With that said, replacing your bent wheel with a brand new one is a better choice in most cases.
Eddie is the co-founder of CarCareCamp.com, and the site’s primary contributor.
Automotive repair has played a major role in his family for generations and he’s determined to continue the legacy further on.
Under his belt, Eddie has a bachelor’s degree in Automotive Electronics Engineering and almost a decade of experience working as an electrician in a major semi-truck dealership overseas.