charge an up-grade at wide open throttle, cruise over the crest at part throttle, and then control your speed down hill by
working the accelerator between Idle and part throttle, as determined by the grade steepness. The Jake Brake retards
the truck by completely fouling-up the valve train and opening the intake valve near top-dead-center of the "power stroke".
The engine becomes an air compressor, driven by the truck's speed and moment um. The Jake Brake provides you with
about 3/4 of the horsepower, for slowing down, that the Cummins provides, for wide-open-throttle acceleration.
For
safety, an immediate change from full engine braking to full acceleration is available by merely depressing the accelerator
treadle. The Jake Brake switches to normal engine idle at stops, preventing engine stalls. You have to use the service
brake to stop the truck. The Jake Brake Is excellent in stop-and-go traffic, in hilly terrain, and on long down grades. The
Jake Brake provides safe, controlled dynamic braking, prevents engine overcooling by adding heat, saves service brakes
for stopping, and greatly increases mileage between brake reline jobs.
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