Read all starting instructions carefully before you start your vehicle.

For temperatures below 32 °F (0 °C), the use of the correct grade engine oil is essential for proper operation. Refer to engine oil specifications for more information.   See   Capacities and Specifications - 6.7L Diesel. 

Your vehicle may have a cold weather starting strategy that prevents severe engine damage by assisting in engine lubrication warm-up. In extremely cold ambient temperatures, this strategy activates and prevents the accelerator pedal from being used for 30 seconds after you start your vehicle. A message appears in the information display as your vehicle warms up. By not allowing the accelerator pedal to be used, the engine oil is allowed to properly lubricate the bearings preventing engine damage due to lack of proper lubrication. After the 30 second warm-up period, the accelerator pedal becomes operational again and a message appears informing you the vehicle is ok to drive.

When you start the engine in extremely cold temperatures -15 °F (-26 °C), we recommend that you allow the engine to idle for several minutes before you drive the vehicle.

 Do not crank the engine for more than 10 seconds as starter damage may occur.If the engine does not start, switch the ignition off and wait 30 seconds before trying again.

The diesel engine glow system consists of:

The powertrain and glow plug control modules electronically control the glow plug system. After you switch the ignition on, the glow plug control module immediately energizes the glow plugs. The glow plug control module uses the engine coolant temperature, barometric pressure sensor and environmental temperature sensor to determine how long the glow plugs stay energized. The required time for the glow plugs to be energized decreases as the coolant temperature, barometric pressure and environmental temperature increase.

If your vehicle is equipped with a keyless ignition, it has a feature that automatically shuts down the engine if it has been idling for an extended period. The ignition also turns off in order to save battery power. Before the engine shuts down, a message appears in the information display showing a timer counting down from 30 seconds. If you do not intervene within 30 seconds, the engine shuts down. Another message appears in the information display to inform you that the engine has shut down in order to save fuel. Start your vehicle as you normally do.

We recommend that the engine block heater be used for starting when the temperature is -9 °F (-23 °C) or colder.   See   Engine Block Heater. 

When operating in cold weather, you may use Motorcraft® cetane improvers or non-alcohol-based cetane improvers from a reputable manufacturer as needed.

Change to a lighter grade engine oil to make starting easier under these conditions. Refer to engine oil specifications.   See   Capacities and Specifications - 6.7L Diesel. 

Diesel fuel is adjusted seasonally for cold temperatures. Diesel fuel which has not been properly formulated for the ambient conditions may gel which can clog the fuel filters. One indication that the fuel filter(s) may be clogged is if the engine starts, stalls after a short time, and then does not restart. If you have been using biodiesel, you may need to use a fuel with lower biodiesel content, try another brand, or discontinue using biodiesel. Do not use alcohol based additives to correct fuel gelling. This may result in damage to the fuel injectors and system. Use the proper anti-gel and performance improvement product.   See   Capacities and Specifications - 6.7L Diesel. 

Your vehicle has a fuel and water separator that recirculates fuel from the engine to help prevent fuel filter clogging. To avoid engine fuel starvation during cold weather operation of 32 °F (0 °C) or below, we recommend that the fuel level in your tank should not drop below ¼ full. This helps prevent air from entering the fuel system and stalling the engine.

Your vehicle has a selective catalytic reduction system that uses Diesel Exhaust Fluid (DEF) to operate properly. You need to replenish your vehicle’s DEF at certain intervals. When filling your vehicle’s DEF tank in cold weather, take special care to prevent damage to the tank.   See   Selective Catalytic Reductant System - Diesel. 

In cold weather below 32 °F (0 °C), the engine may slowly increase to a higher idle speed if you leave it idling in park (P). As the engine warms-up, the engine sound level decreases due to the activation of PCM-controlled sound reduction features.

If you operate your vehicle in a heavy snowstorm or blowing snow conditions, snow and ice can clog the engine air induction. If this occurs, the engine may experience a significant reduction in power output. At the earliest opportunity, clear all the snow and ice away from inside the air filter assembly. Remove the air cleaner cover and the air filter and remove any snow or ice. Remove any debris, snow or ice, on the foam filter by brushing the surface with a soft brush. Once you have cleared all of the debris, reinstall the air filter and cover.

Do not use water, solvents, or a hard brush for cleaning the foam filter.

The following information is a guideline only and is not to be the only source of possible solutions in resolving extreme cold temperature issues.

The use of the factory engine block heater assists in engine starting in extreme cold ambient temperatures   See   Engine Block Heater. 

Your vehicle may have a factory option for a stationary elevated idle control through the upfitter switches in the overhead console. This allows the operator to elevate the idle RPM for extended idle periods, as well as aftermarket equipment such as PTO operation. You must configure this feature even if ordered from the factory. See your authorized dealer for required upfitting.

Vehicle operation in heavy snowfall or extreme rain conditions may feed excessive amounts of snow or water into the air intake system. This could plug the air filter with snow and may cause the engine to lose power and possibly shut down.

We recommend the following actions after operating your vehicle up to 200 mi (320 km) in snowfall or extreme rain:

Refer to Air filter and restriction gauge in the Maintenance chapter for more information.   See   Changing the Engine Air Filter - 6.7L Diesel. 

Ingestion of water into the diesel engine can result in immediate and severe damage to the engine. If driving through water, slow down to avoid splashing water into the intake. If the engine stalls, and you suspect ingestion of water into the engine, do not try to restart the engine. Consult your dealer for service immediately.

Your fuel tank vents to the atmosphere by valves on top of the tank and through the fuel cap. If water reaches the top of the tank, the valves may pull water into the fuel tank. Water in the fuel can cause performance issues and damage the fuel injection system.