You may have seen green caps on the tires of your vehicle and wondered what they meant. These called green tire caps and they serve a very important purpose. In this blog post, we will explain what they are and why they are used.
So, what do green caps on tires mean? A green cap on a tire means that the tires are filled with nitrogen, which keeps tires inflated longer and more consistently than regular air.
This is important because it helps to improve fuel efficiency and can extend the life of your tires.
Why Use Green Tire Caps?
There’s no specific reason that green tire caps are used to signal that a tire is filled with nitrogen – the color green was just picked as a different color so you can easily tell a nitrogen-filled tire from a regular-air-filled tire.
Why Use Nitrogen In Tires?
Nitrogen is used in tires because it doesn’t expand and contract as much as regular air does. This means that the pressure in your tires will stay more consistent, which can help with fuel efficiency and tire life.
Additionally, nitrogen doesn’t contain any moisture, which can also lead to increased tire life.
Nitrogen’s slow-moving particles result in a more solid-feeling tire, which results in better vehicle handling.
Consistency in air pressure within the tire also benefits you from improved fuel regulation and efficiency.
Cons Of Nitrogen In Car Tires
When you get a new set of tires, the shop may offer to fill them with nitrogen instead of regular air.
Part of the reason for this is that they know you’ll be back in to visit them, as there are not as many nitrogen tire filling options available versus regular pressurized air.
The main drawback of using nitrogen is that it costs more than regular air to fill your tires.
Where To Fill Green-Capped Tires With Nitrogen
You can typically only fill up nitrogen at tire shops.
Costco also recently started offering free nitrogen tire filling at their stores for members.
Many automotive centers also have nitrogen filling services available.
Do I Need To Fill My Tires With Nitrogen
There’s no rule saying you must use nitrogen, unless you really want those green tire caps.
There are a few high performance vehicles such as the Audi A8, Chevy Corvette, and Ford Mustang GT whose manufacturers require that nitrogen be used in their tires.
Can You Add Air To Tires Filled With Nitrogen?
So, can you mix air and nitrogen in tires?
Yes, nitrogen is fully compatible with regular air, so you can add air to tires filled with nitrogen without worry.
In fact, “regular” air from a compressor contains 78% nitrogen, with the remainder made up of 21% oxygen and 1% of other gases.
It’s called “pure” nitrogen when the nitrogen content is 93% or higher.
Green Cap Tire Inflation – How Much Nitrogen Should I Add?
There’s no difference in the amount of tire pressure you need when filling with pressurized air vs nitrogen, so if your tires have green tire caps, go ahead and fill them per the manufacturer’s specifications.
You can find the recommended tire pressure level on a sticker on the driver’s side door of your vehicle or in your vehicle’s owner’s manual.
There’s also a max tire pressure indicated on the sidewall of your tires – do not exceed this maximum when inflating your tires.
You can use a tire pressure gauge to determine the tire pressure when filling your tires with nitrogen or air.
What Are Green Tire Caps? Wrapping Things Up
So there you have it – now you know what green caps on tires mean! Keep an eye out for them, and you’re sure to notice them way more than before.
If you have green tire cap envy, don’t worry. While nitrogen is not required, it can be a helpful addition to your vehicle.
If you are considering filling your tires with nitrogen, be sure to ask your mechanic or tire dealer about the benefits and drawbacks.
Thanks for reading! We hope this blog post was helpful in explaining what those green caps on tires mean. Drive safe!