Single vs Dual Overhead: The Differences

Truckers will be busier than ever this holiday season, as everyone is shopping online. For this reason, fleet employees are primarily focused on completing their routes instead of stopping to think about the magnificent vehicles they’re driving. The truth is, if drivers stopped to realize how complex their trucks’ engines are, they’d realize they can make adjustments to improve efficiency. One thing they can do is decide between single or dual overheads; this piece will explain the differences between the two.

What Is the Difference?

Before explaining the differences between single vs. dual overheads, it’s vital to discuss what these components are. Essentially, overheads are the camshaft of a vehicle. A camshaft is a rod-shaped structure that operates on a timed schedule to release the air/fuel mixture needed for combustion. It sounds like a mouthful, right? It’s actually simpler than one may think. The difference between a single vs. dual overhead is the number of valves attached to each part. Dual overheads have more valves that might improve the combustion process.


Dual overheads typically have more power than single alternatives because there are more valves. Since combustion can occur in several different places, automobiles with dual overheads have more horsepower. Still, this additional power does come at a cost.

Fuel Efficiency and Weight

Single overheads have better fuel efficiency than their dual counterparts because the engines don’t have to work as hard. Furthermore, dual overheads add weight to the automobile. The heavier a truck is, the more gas it’ll burn. Trucking fleet owners should keep this in mind if they’re trying to cut down on costs.

Since dual and single overheads play such an integral role in an engine’s efficiency, they must be working properly at all times. Anyone who notices issues with their truck’s power or fuel efficiency should contact ATL Diesel right away. We have top-of-the-line Caterpillar engine parts that will help repair large vehicle issues. We want every trucker to get back on the road as quickly as possible so that every holiday gift gets delivered.