Allison Transmission offers parallel hybrid architectures for a wide range of commercial vehicles, including transit and city buses and medium-duty trucks for distribution, refuse, utility and shuttle bus applications.

With thousands of Allison hybrid propulsion systems in operation worldwide, we are the world’s largest producer of hybrid systems for transit and city buses.

Unique Allison hybrid propulsion systems allow efficient regenerative braking and deliver reduced fuel consumption with fast and smooth acceleration. We provide the performance and reliability you need and the increased fuel economy and lower emissions you want.


Allison Transmission has been a pioneer in hybrid and electric propulsion systems since 1989 when we contributed to General Motors’ revolutionary electric car. From there, we integrated our electric vehicle experience with our commercial vehicle knowledge to create an Allison hybrid system for transit and city buses, which operates in hundreds of cities worldwide.

Allison hybrids are designed and engineered for full regenerative braking, higher performance and reduced emissions. From transit and city buses to medium-duty distribution, refuse and utility vehicles, Allison hybrids provide a smooth, efficient ride. And from fuel savings to environmental responsibility and efficiency, the benefits of an Allison hybrid add up to the perfect solution for your challenges.

Read below to learn how an Allison hybrid can provide improved fuel economy, faster acceleration, and superior reliability and durability.

Fuel Economy and Reduced Emissions

When decelerating or stopping, an Allison hybrid system converts a vehicle’s kinetic energy to stored electric energy – making the electrical motor act as a generator. This energy is stored in battery packs for later use to propel the vehicle or operate auxiliaries. 

With an Allison hybrid system, you will experience reduced emissions and fuel savings up to 25% depending on the vocation and duty cycle.

And with the regenerative braking system, the vehicle’s brake life is extended up to three times.

Fast, Smooth Acceleration

A bus equipped with an Allison H 40/50 EP™ hybrid system benefits from its continuous variable drive and can accelerate equal to or better than a similar bus equipped with a conventional drivetrain.

Proven Reliability and Durability

Allison products are known for performing reliably in tough duty cycles such as those in transit and city bus as well as in medium-duty distribution, refuse and utility applications. We have worked for decades to build some of the most reliable transmissions in the world, and we transferred this experience to our hybrid system designs. The fact is, a vehicle sitting in the shop is costing you money – repairs are expensive and productivity is lost. 

That’s why Allison builds our transmissions to last. 

Hybrid Solaris Urbino bus equipped with an Allison transmission


For transit and city bus applications, Allison H 40/50 EP™ hybrid systems have proven to be some of the most dependable and efficient hybrid propulsion systems at work anywhere in the world. In full production since 2003 and now operating in thousands of buses around the world, the Allison hybrid systems offer up to 25% fuel savings depending on the duty cycle.

MODELS + Ratings

Allison offers several model choices, giving you ultimate control over selecting the features and power you need for your school bus fleet.

Reference the specification information below to compare all of our transmission models in the Hybrid Bus Series and find the one that best meets your business needs. Information and specifications subject to change without notice or obligation. Please check with your vehicle salesperson to ensure offerings.

Specification Download

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Hybrid Bus Brochure

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