Based on the Cummins B Series, the ISB engine was launched in 1998 and is available in 4 and 6 inline cylinder models. Design innovations include a 24-valve setup and the Interact electronic engine management system, both contributing to increased fuel efficiency and meeting emission regulations.
A few years later, the QSB (Quantum System) was introduced to comply with even stricter U.S. Environmental Protection Agency standards.
ISB engines are used in light-duty trucks and emergency vehicles; QSB models are utilized in marine, agricultural, and construction applications as well.
We carry a large assortment of new and remanufactured parts for ISB 3.9, ISB 5.9, QSB 4.5, QSB 5.9, and QSB 6.7 diesel engines.
For more information on ISB/QSB engines, please visit our Cummins engine specifications page.