Are All Gas Caps The Same?

The gas cap is a simple and straightforward part. It has very few moving components. It's only a cap that covers the fuel tank. That's why some people are under the impression that they can grab the first replacement gas cap they see and then call it a day.

It's actually not that simple. If you have a gas cap that needs replacing, you must get one with proper fitment. Different OEM and aftermarket brands have different fitments. For example, a Ford Taurus gas cap might not fit a Subaru Outback.

What Happens When You Get An Ill-Fitting Gas Cap For Your Subaru

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Like we discussed in this blog post, quite a few issues can arise when your gas cap fails. A gas cap's job is to cover the opening to the fuel tank, so an ill-fitting cap is one that has failed its purpose. Some of the most common issues that may happen as a result of an ill-fitting cap include:

• Fuel will evaporate from the tank and pollute the environment.
• Your Subaru's fuel economy will suffer.
• If your Subaru makes any sudden and aggressive movements, fuel may spill out of the tank.
• The fuel can get contaminated by dirt and moisture entering the tank. This can lead to expensive problems such as fuel pump failure.
• Your Subaru may have a hard time passing emissions. An ill-fitting gas cap can cause the check engine to come on.

That's why it's important to get the right replacement gas cap for your car. Do you want your new gas cap to last a long time without creating any issues? Get a high quality one with proper fitment. OEM gas caps fit the bill.

Subaru Builds OEM Gas Caps With The Right Specs

As long as you get an OEM gas cap made for your particular Subaru model, you don't have to worry about any fitment issues. Subaru has all the specs for your vehicle, so an OEM gas cap will always have the correct fitment.

1. The opening of the cap must be the same diameter as the filler pipe so that it does not interfere with the fuel tank opening. An OEM gas cap will allow for pressure relief. It's so excess pressure doesn't get trapped within the tank due to changes in temperature or atmospheric conditions.
2. The gas cap must have the correct threading to fit your Subaru's filler pipe and keep it sealed. Otherwise, the cap may fall off and/or fuel may leak out. The gas cap must have the correct amount of threads and the correct spacing.

Aftermarket gas caps may look the same as an OEM caps, but they don't always function the same. For example, you could end up with a different threading or diameter opening on your aftermarket cap. That can lead to fuel spilling out and other problems.

Aftermarket manufacturers don't always follow OE specs. In fact, many gas caps are universal. That's something you should avoid.

Subaru Uses High Quality Materials When Building Its Gas Caps

Not only do Subaru gas caps have the correct specs, they're also made with high quality materials. This means an OEM gas cap won't corrode and deteriorate over time.

You can't say the same thing about aftermarket gas caps. They're often made with inferior materials. They may rust or break apart in a short amount of time. Their threading could be poor quality. The seal may be poor quality and fail to seal correctly, which can lead to fuel spilling out when you're filling up at the pump.

Summing Up

Replacing a gas cap is not difficult, but getting an ill-fitting one can lead to a number of problems. There's no reason why you should take any chances with your Subaru. It will only make things worse.

So if you need a replacement gas cap, get one with proper fitment for your Subaru. That means getting an OEM cap. At SubaruPartsPlus.com, we carry genuine OEM Subaru gas caps for many different Subaru models. Please contact us if you need help finding the right replacement gas cap for your Subaru.