The vehicle's diesel engine starts differently than a gasoline engine. Read the following pages to learn how to start, restart, warm-up, and stop the diesel engine.

The information applies to Caterpillar® Diesel Engine , 6.6L DURAMAX® Diesel Engine, Isuzu 6H Diesel Engine, unless otherwise noted.

If you have a Caterpillar® Diesel Engine, also refer to the Caterpillar® Diesel Engine Operation & Maintenance Manual for the starting procedure.

Move the shifter to P (Park) or N (Neutral). The engine will not start in any other position. To restart the engine when the vehicle is already moving, use N (Neutral) only.

Notice: Do not try to shift to P (Park) if the vehicle is moving. If you do, you could damage the transmission. Shift to P (Park) only when the vehicle is stopped.

Move the shift lever to N (Neutral) and hold the clutch pedal to the floor while starting the engine. The vehicle will not start if the clutch pedal is not all the way down.

1. Turn your ignition key to ON/RUN.

Observe the wait to start light. See Wait to Start Light. This light may not come on if the engine is hot.

If you have a Caterpillar® diesel engine, see your Caterpillar® Diesel Engine Operation & Maintenance Manual for proper wait to start light operation.

2. As soon as the wait to start light goes off, immediately turn the ignition key to START. When the engine starts, let go of the key.

If the vehicle is equipped with a DURAMAX® 6600 Diesel Engine, it has a fast warm-up glow plug system. The wait to start light will illuminate for a much shorter time than most diesel engines, due to the rapid heating of the glow plugs.

Notice: Holding the key in START for longer than 15 seconds at a time will cause the battery to be drained much sooner. And the excessive heat can damage the starter motor.

Notice: If the wait to start light stays on after starting the vehicle, the vehicle may not run properly. Have the vehicle serviced right away.

3. If the engine does not start after 15 seconds of cranking, turn the ignition key to OFF. Wait one minute for the starter to cool, then try the same steps again.

If you are trying to start the engine after you have run out of fuel, see Running Out of Fuel.

When the engine is cold, let it run for a few minutes before you move the vehicle. This lets oil pressure build up. The engine will sound louder when it is cold.

Notice: If you are not in an idling vehicle and the engine overheats, you would not be there to see the overheated engine indication. This could damage the vehicle. Do not let the engine run when you are not in the vehicle.

If the vehicle has the 6.6L DURAMAX® Diesel Engine or the Isuzu 6H Diesel Engine, the following notice applies:

Notice: The diesel engine has an electric air intake heater system which reduces white smoke and helps start the engine in cold weather. Do not spray starting fluid into the air intake where it can contact the heater elements.

The following tips will help with engine starting in cold weather.

Because the diesel engine uses compression ignition, it is harder to start in cold weather than a gasoline engine. The air intake heater, use of the proper engine oil, optional engine coolant heater and optional ether injection system help cold weather starting. See the Caterpillar® Diesel Engine Operation & Maintenance Manual for more information.

If you have to restart the engine while the vehicle is moving, shift to N (Neutral).

1. Apply the parking brake. See Parking Brake for parking brake apply procedure.
2. Shift into N (Neutral) for a manual transmission or P (Park) for an automatic transmission.
3. Turn the ignition key to OFF.

If the vehicle has a two-speed axle, see Two-Speed Rear Axle.

If you have a Caterpillar® diesel engine, see the Caterpillar® Diesel Engine Operation & Maintenance Manual for additional information.

Several factors affect how quickly the diesel engine warms up. These can include outside temperature, engine load, idle time and the vehicle's option content. The vehicle may be equipped with some features that can help the engine reach operating temperature sooner. Some of these features are discussed below.

Also, remember that an automatic transmission adds heat to the cooling system through the heat exchanger in the radiator. Because of this, vehicles equipped with automatic transmissions are often able to retain engine coolant heat better than manual transmission vehicles.

See the Caterpillar® Operation & Maintenance manual for additional diesel engine warm-up information.

If you have run out of fuel, see Running Out of Fuel.

If you are not out of fuel, and the engine will not start, do this:

Turn the ignition key to ON/RUN. Immediately after the wait to start light goes off, turn the ignition key to START.

If the light does not go off, wait a few seconds, then try starting the engine again. And, see your dealer/retailer as soon as you can for a starting system check.

If the light comes on and then goes off and you know the batteries are charged, but the engine still will not start, the vehicle needs service.

If the light does not come on when the engine is cold, the vehicle needs service.

If the batteries do not have enough charge to start the engine, see Battery.

Be sure you have the right oil for the engine, and that you have changed the oil at the proper times. If you use the wrong oil, the engine may be harder to start.

Be sure you are using the proper fuel for existing weather conditions. See What Fuel to Use.

If the engine starts, runs a short time, then stops, the vehicle needs service.

Caution: Do not use gasoline or starting aids, such as ether, in the air intake. They could damage the engine. There could also be a fire, which could cause serious personal injury.