Our Dyno Test Erases Worries About Your On-Highway Engine’s Performance

If a car’s engine fails to put out the manufacturer cited horsepower, that’s likely to get a shoulder shrug from the owner. A commercial truck, however, needs to hit those performance standards, otherwise the owner loses money.

The dyno testing center at our On-Highway shop in Kent, Washington, assures truck owners that the engine in their rig hits key performance benchmarks, including horsepower ratings. The testing is critical for someone looking to buy a used truck or suspects their truck needs repairs.

“It’s an excellent way of knowing the current status of the engine,” said Pat Ryan, Service Manager at our On-Highway shop in Kent. “It removes questions about whether you’re having fuel consumption or horsepower issues and gives you peace of mind regarding the condition of the engine.”

The Dyno Machine

The dynamometer machine we use is a single roller style that allows our factory-trained technicians to simulate road conditions in a controlled environment. The machine gives us the flexibility to test the drive axles simultaneously or independently. The roller set up also allows to test the front or back set of the drive axles for vehicles with a longer wheel base.

Confidence Booster

The most common dyno test we perform is for someone interested in buying a used truck. We’ll put the truck onto the dyno machine and after prepping for the test, run the engine for 15 to 20 minutes. The session gives us data on the crankcase pressure, peak horsepower, torque and, most importantly, engine output.

The results let the owner know how the engine is performing when graded against factory recommendations.

Something is Wrong

The second most common dyno test we perform for customers is a truck owner who suspects something is wrong with their rig and wants confirmation. We’ll test the speed, load, engine rpms and in some cases the pressure.

In both tests, we’ll also run engine diagnostics to complement the information we gather during the dyno run.

Important Measurements

In both cases, the owner comes away with solid information about the engine’s performance, Ryan said.

“They’ll know if the cylinders are still good enough to hold pressure and whether they’re getting the advertised horsepower,” he said.

If there are any problems, they have the option to have our factory-trained technicians make the appropriate repairs.