Which of the following engine brakes offers progressive step braking using from one to all six cylinders?

The Cummins Intebrake on pre-2010 ISX engines is designed to provide progressive step braking, which allows the operator to engage any number of the engine's six cylinders to adjust the level of braking force. This feature enables control over the braking intensity based on the operational needs. For instance, the driver can use one cylinder for gentle braking and engage more cylinders as needed for greater braking power, effectively allowing for a smoother and more responsive braking experience.

This type of engine brake system is particularly advantageous for maintaining stability and control during deceleration, especially when descending grades or when load management is critical. Each cylinder can be activated independently or in groups, making it versatile for different driving situations.

Other engine brake systems do not offer the same level of progressive control. For instance, while the Jacobs brake is known for its effectiveness, it may not provide the same seamless, multi-cylinder engagement as the Cummins Intebrake, which is specifically designed for this purpose. Similarly, the Mercedes-Benz CTV and Caterpillar BrakeSaver, while effective in their own respects, do not feature this unique capability of progressively increasing braking force based on cylinder engagement.