What Type Of Engines Do School Buses Have Under The Hood?

School buses are built to be a safe and durable mode of transportation for students around the world. But have you ever wondered what powers these buses? While the outside of a school bus hasn't changed much over the years, the engine under the hood that keeps these yellow giants moving might surprise you.

Cummins offers a range of durable school bus engines running on either diesel, gasoline, or natural gas. Their selection includes the 300-horsepower B6.7 Octane, the 260-to-350-horsepower L9, and the ISB6.7 G with up to 240 horsepower. But Ford's monster 7.3-liter Godzilla V8 — which the company also uses in the Super Duty, F-650, and F-750 trucks — is perhaps the most impressive school bus engine on the road, with a maximum power output of 350 horsepower.

IC Bus is one of the school bus manufacturers that uses the Cummins B6.7 and L9 engines in their diesel buses, while the Blue Bird Corporation uses the Godzilla engine when building its buses. Thanks to a deal with Ford, Blue Bird is the only school bus manufacturer that uses the Godzilla engine.

School buses are primarily powered by traditional engines that run on fossil fuels, but that's beginning to change thanks to new technological advancements. Around 5,000 electric school buses had started transporting students in the U.S. by fall 2024, with more new buses coming in 49 states. Unlike their gas and diesel-powered counterparts, vehicles like the Daimler electric school bus have no tailpipe emissions and are thus more eco-friendly.

Existing school buses can also be converted, or repowered, from traditional engines to electric, with a similar conversion happening on new buses that have yet to enter service. These electric repowers must align with the vehicle's other systems in order to be successful.

Hybrid school buses are also a viable option compared to gas and diesel buses. The first such diesel-electric hybrids rolled out in Manatee County, Florida, in 2007 and were built by IC Bus and Enova Systems. Several other states followed, including Pennsylvania in 2007, Iowa in 2008, and Michigan in 2010.