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  • Gasket sizing is fairly straightforward if your vehicle’s running on its original exhaust system. Simply pick the gasket type you need and search for one that’s tailored to your vehicle’s make and model.
  • If you’re running a customized exhaust system in your vehicle, you’ll need to bust out the tape measurer and note down all your old gasket’s measurements. You’ll either need to search for an aftermarket gasket that fits those measurements or have one custom-made.
  • The different exhaust pipe gasket types include the exhaust manifold gasket, the collector gasket or exhaust flange, the header gasket, and the pipe gasket.

Your vehicle’s exhaust system is equipped with several gaskets along its exhaust pipes, all of which can vary greatly in size and shape. These exhaust pipe gaskets prevent exhaust gas from leaking out of the system, with certain gaskets serving other purposes, like preventing exhaust noise or indirectly cutting down emissions. There are different types of gaskets that belong in various parts of the exhaust system, and different vehicles require distinct gasket sizes even for gaskets of the same type. So before you buy any new gaskets to repair that leak in your system, it’s best to know what you’re looking for.

Gasket Sizing Summarized

Gasket sizing ranges from fairly straightforward to incredibly difficult. First, you need to know what your vehicle’s exhaust system is like. If you’ve never had custom work done on your exhaust system, then that means you can likely go for factory gasket sizes. However, if your vehicle has a customized exhaust system, you might need custom gaskets to suit its unique needs.

Factory Gasket Sizes

When buying gaskets for your original equipment manufacturer (OEM) exhaust system, you can typically find the right gasket size by looking for gaskets that’ll fit your vehicle’s year, make, and model. Most aftermarket sites will list what vehicles their gaskets were manufactured for. It’s simple and straightforward. You don’t need to measure anything. Simply pick the gasket type you need and search for one that’ll fit your vehicle.

Custom Gasket Sizes

For customized exhaust systems, you’ll have to retrieve the faulty gasket first. Measure the inner and outer diameter of the gasket and note down the measurements. Then, measure the bolt-hole spacing. For circular exhaust flanges, you’ll also need to measure the distance from the center of one bolt hole to the center of the bolt hole that sits directly across from it. If the gasket isn’t circular, you’ll need to take care and measure all the different sides and corners to ensure the gasket you buy properly matches up with your system.

Once you have all the gasket measurements down, you can start searching for an aftermarket exhaust gasket that matches them exactly. If you can’t find any, you can always have the parts custom-made.

Exhaust Gasket Types and Uses

When attempting to find the right gasket size to buy, it’s also helpful to know the different exhaust gasket types.

Exhaust Manifold Gasket

Exhaust manifold gaskets are typically found between the engine’s cylinder head and the exhaust manifold itself. If your vehicle has more than one exhaust manifold, it also has more than one exhaust manifold gasket. Because they’re situated in an area with high temperatures and extreme pressure, exhaust manifold gaskets are typically multilayered and made from sturdy materials like composite graphite and multilayer steel. The most common exhaust gasket material is embossed steel.

Collector Gasket or Exhaust Flange

The collector gasket, also known as the exhaust flange, connects the exhaust pipe to other parts of the exhaust system like the muffler and catalytic converter. Exhaust flanges are able to connect different parts through the use of a gasket and a set of bolts at each flange. They’re made to withstand lots of heat expansion and vibration in the exhaust system and are also made of the same materials as exhaust manifold gaskets.

Header Gasket

Header gaskets are typically found in customized aftermarket exhaust headers. They take the place of exhaust manifolds and seal the area between the engine’s cylinder head and the exhaust header. The added performance boost from using an exhaust header means these gaskets need to withstand even higher pressure and temperatures than the typical manifold gasket. As a result, header gaskets use materials that are even more resilient to these conditions, like copper and certain composites.

Pipe Gasket

Pipe gaskets join parts of the exhaust pipe together. They seal the different sections of the exhaust pipe and prevent leaks along the line. They also need to withstand high temperatures and pressure and are made using the same materials as exhaust manifold gaskets.

Exhaust pipe gaskets are a small but important part of your vehicle’s exhaust system. Without them, exhaust gases would easily escape between sections of the exhaust pipe and near where it connects to the different components. Buying new gaskets is simple if you use an OEM exhaust system, but it can get complicated if you use a customized system. In the end, make sure you double-check your custom gasket’s measurements or your vehicle’s make and model before making your purchase.

About The Author
Written By Automotive and Tech Writers

The Research Team is composed of experienced automotive and tech writers working with (ASE)-certified automobile technicians and automotive journalists to bring up-to-date, helpful information to car owners in the US. Guided by's thorough editorial process, our team strives to produce guides and resources DIYers and casual car owners can trust.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.

File Under : Exhaust System , DIY
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