Engine Brake Operation

108SD d 10.04.001

Depending on the brake type, the engine brake may be disabled when engine temperature falls below a set level.

Notice: Do not allow the engine to exceed 2500 rpm. Serious engine damage could result.

To activate the engine brake after the engine is warmed up and the vehicle is in motion:

Remove your feet from both the clutch and throttle pedals.
Press the On/Off switch to toggle the engine brake on. See Fig.. The engine brake will engage at the rate last set on the brake intensity switch.
Move the intensity switch to the desired intensity.
On vehicles with a HI/MED/LO intensity switch, LO will provide 1/3 of the full braking capacity of the engine, MED will provide 2/3 of the full braking capacity, and HI will provide maximum engine braking. On vehicles with a HI/LO intensity switch, LO will provide ½ of the full braking capacity of the engine; HI will provide maximum engine braking.
Use the intensity switch set at the LO position when driving on flat, open stretches of road. If the service brakes are still required to slow down on a grade, switch to a higher setting on the dash switch until there is no need for the service brakes. Grade descent speed should be such that the service brakes are used infrequently and remain cool, thus retaining their effectiveness.
For maximum retarding, maintain the top governed speed of the engine through the appropriate selection of gears. When shifting gears, the engine brake will disengage when the clutch pedal is depressed, then engage when the clutch pedal is released.
To cancel the engine brake application, toggle the On/Off to off.
Fig. 1, Engine Brake Switches

Note: