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Everyone’s heard the recommendation to “work smarter, not harder,” and one way this can be achieved is to make use of the resources that are available to you. Have you found yourself thinking that finding values like a gear ratio or an engine RPM would be easier with a simple digital tool? Online, you can find free calculators that will help you quickly determine important values such as your engine RPM, gear ratio, and how much fuel you can save across a fleet of commercial vehicles based on lube choice.

Using valuable tools like these rather than crunching the numbers yourself can contribute to a more streamlined workflow and ensure that you never have to guess at important calculations.

Determine Your Engine’s RPM

When you start your engine, the pistons begin to rotate the crankshaft as they move up and down. Every time the crankshaft finishes a 360-degree rotation, it’s known as a revolution. A measurement of revolutions per minute, or RPM, indicates how fast the engine is turning. Knowing your engine RPM helps you determine whether your engine and transmission are running properly and can help you increase your vehicle’s mileage by shifting gears at the correct RPM level, among other things.

You can measure your engine’s RPM with this online engine RPM calculator based on the gear ratio, speed, and tire height. For this calculator, the speed can be logged as MPH or KPH and the tire height in inches or millimeters. If you’re not sure of the gear ratio, a gear ratio calculator can help determine that. In case you are unsure of the transmission type, this calculator delivers results in terms of automatic in drive and overdrive, 3-speed manual in 3rd gear, and 5-speed (or higher) manual transmission in the last gear. When you monitor your RPM and shift according to recommended methods, you’ll enjoy the best possible vehicle performance.

Calculate a Gear Ratio

The gear ratio of your vehicle is one factor that determines its top speed, how long it takes to achieve that speed, and how hard it works to get there. If you’re performing any modifications on your vehicle, it’s important to keep gear ratio in mind to help make decisions about performance versus fuel economy.

For the best fuel economy, a “lower” gear ratio is associated with a lower number of revolutions that the engine turns for each turn of the axle. A lower gear ratio means the vehicle will have a slower acceleration rate, as the final drive ratio has been optimized for highway speeds. However, if you’re looking for high performance—like greater acceleration or increased towing power—you may consider a numerically higher axle ratio. This delivers a mechanical advantage, sending more of your engine’s available torque to the tires.

You can calculate the gear ratio by dividing the number of ring gear teeth by the number of pinion gear teeth. Or, you can determine the ratio between the ring gear and pinion gear in the rear end axle of your vehicle with this free online gear ratio calculator.

See How the Right Lube can Increase Fuel Economy

Using a fuel-efficient synthetic gear lubricant for every vehicle in a commercial fleet can add up to savings, both for your bottom line and for the environment. In terms of financial savings, the right lube can deliver up to a 1% fuel savings annually. That improved fuel economy can translate to lower CO2 emissions for a greener fleet.

With the fuel savings calculator found on, you can enter the number of trucks in your fleet, the average number of miles driven, your average cost per gallon of fuel, and  current average miles per gallon (MPG). This tool will then deliver clear-cut dollar savings amounts and potential MPG results, demonstrating how your fleet could be more profitable with a high-quality lubricant. And if you choose Spicer® FE75W-90 fuel-efficient synthetic gear lubricant, you’ll enjoy longer gear life, better operating performance, and the option to extend your carrier warranty—in addition to quantifiable fuel savings.

Tools to Help You Succeed

Your job is challenging enough already, so Dana Aftermarket invites you to make use of our free, online calculators. They can help increase efficiency and simplify your day-to-day procedures. Use any web-enabled device to access our engine RPM calculator, gear ratio calculator, fuel savings calculator, and other useful resources instantly at