Rain Caps

What Is an Exhaust Rain Cap? 

An exhaust rain cap is an essential part of your truck’s exhaust system. It protects the exhaust system from rain, snow, downdrafts, animals, and birds. Without caps, you leave your exhaust system vulnerable to rust and blockages. 

Truck Pipes USA carries a wide range of exhaust rain caps, including popular 3-, 4-, and 5-inch models. 

How Does an Exhaust Rain Cap Work?

Commercial trucks and other vehicles with vertical pipes have rain caps attached to the exhaust pipe with a hinged flapper. This exhaust flapper keeps the cap closed when the engine is off. When it’s running, gas pressure pushes the cap open to release the exhaust.

What Types of Pipes Use Rain Caps? 

Truck Pipes USA carries aluminized steel exhaust pipes, chrome straight exhaust pipes, and others that match our selection of rain caps. Choose from multiple finishes, including chrome, zinc-plated, and polished stainless steel. 

Because rain caps are most commonly used on semi-trucks, buses, and other commercial vehicles with vertical exhaust stacks, we have a large variety of caps for these pipes. 

We also carry rain caps for stationary and industrial engines, including construction equipment, farming equipment, marine engines, and others. 

How Do I Install a Rain Cap? 

Choose a rain cap that fits snugly over your exhaust pipe. Place the exhaust cap on the tip of the pipe and tighten the bolt until it’s snug. 

Test the cap to see whether the exhaust rain flap can move freely up and down. If your cap is too tight, exhaust gas could get stuck in the pipe. 

How Do I Choose the Right Size? 

Measure the outer diameter of your exhaust pipe using a flexible tape measure. Choose a rain cap with a collar range that includes your specific size. If you can’t measure your exhaust pipe, look at your owner’s manual or research your particular vehicle online to find the measurement.