NOx Sensor

Nitrogen monoxide and nitrogen dioxide, collectively known as NOx, are some of the most dangerous byproducts of diesel combustion. Keeping these pollutants out of your exhaust is necessary both for ensuring community safety and passing emissions testing.

At Truck Pipes USA, we don't think you should have to choose between quality and affordability. We work hard to bring you quality NOx sensors and other exhaust components at affordable prices.

What Is a NOx Sensor?

A NOx sensor's job is straightforward: monitoring nitrogen monoxide and nitrogen dioxide and relaying that information to your truck's selective catalytic reduction, or SCR, system.

Most trucks have one NOx sensor located upstream of the SCR and one located downstream. Information from the upstream sensor is used to calculate the amount of catalyst that the SCR needs to inject, and the downstream sensor shows how much NOx your truck is venting into the atmosphere.

NOx sensors use a two-chamber electrochemical design. The first chamber removes excess oxygen from the exhaust, and the second chamber measures a current that is proportional to the amount of NOx present. This allows the control module to calculate the concentration of NOx in the exhaust stream.

Because of their location in the heart of the exhaust system, NOx sensors get battered by plenty of abrasive soot. Over time, the soot both coats and damages the sensors, meaning it's time for a replacement.

Reducing Emissions in Your Semi Truck

The SCR system injects diesel exhaust fluid, or DEF, into a chamber to combine with the NOx in the exhaust gases. DEF is made up of urea, a nitrogen-based compound, and water. When mixed with exhaust at high temperatures, it turns dangerous nitrogen monoxide and nitrogen dioxide into harmless nitrogen gas and water vapor.

The amount of DEF matters. If there's too little, the NOx can't decompose and remains in your emissions. If there's too much, you're wasting DEF and money. Data from your NOx sensors is critical for getting the balance right.

Browse Our Selection

At Truck Pipes USA, we stock NOx sensors for a wide range of engine makes, including:

• Cummins
• Isuzu
• Detroit Diesel/Mercedes-Benz
• Volvo

All of our sensors are made in North America by top aftermarket brands, including Dinex and Redline Emissions Products. These components are designed to fit just as well as OEM parts for a fraction of the price.

Why Choose Truck Pipes USA?

Being an owner-operator or fleet manager is hard work. At Truck Pipes USA, we want to help make your job easier by offering a wide selection of reliable and affordable aftermarket parts for your truck's exhaust system.

We're no fly-by-night company, either. We stand behind all of our products, and our US-based customer service team is ready to help you find the right part. Our fast service and expedited shipping options get you back on the road fast, and with free shipping on all orders over $99, it's easy to get everything you need. Whether you're replacing a NOx sensor or installing a whole new exhaust system, we have you covered.