Engine Compartment Overview
Battery and Engine Components
- Positive (+) Terminal (Under Cover). See Jump Starting - North America.
- Battery - North America.
- Engine Compartment Fuse Block.
- Engine Oil Dipstick. See “Checking Engine Oil” under Engine Oil.
- Engine Cooling Fans (Out of View). See Cooling System.
- Engine Oil Fill Cap. See “When to Add Engine Oil” under Engine Oil.
- Coolant Surge Tank and Pressure Cap. See Cooling System.
- Engine Air Cleaner/Filter.
- Brake Fluid Reservoir. See Brake Fluid.
- Windshield Washer Fluid Reservoir. See “Adding Washer Fluid” under Washer Fluid.
Engine Oil
For diesel engine vehicles, see “Engine Oil” in the Duramax diesel supplement. To ensure proper engine performance and long life, careful attention must be paid to engine oil. Follow these steps:
- Use engine oil approved to the proper specification and of the proper viscosity grade. See “Selecting the Right Engine Oil”.
- Check the engine oil level regularly and maintain the proper oil level. See “Checking Engine Oil” and “When to Add Engine Oil”.
- Change the engine oil at the appropriate time. See Engine Oil Life System.
- Always dispose of engine oil properly. See “What to Do with Used Oil”.
Checking Engine Oil
Check the engine oil level regularly, every 650 km (400 mi), especially prior to a long trip. The engine oil dipstick handle is a loop.
Warning: The engine oil dipstick handle may be hot; it could burn you. Use a towel or glove to touch the dipstick handle. If a low oil Driver Information Center (DIC) message displays, check the oil level.
Follow these guidelines for accurate readings:
- Park the vehicle on level ground. Check the engine oil level after the engine has been off for at least two hours.
- If unable to wait two hours, the engine must be off for at least 15 minutes if warm, or 30 minutes if cold. Pull out the dipstick, wipe it clean, then reinsert and check the level.
When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of the dipstick and the engine has been off for at least 15 minutes, add 1 L (1 qt) of the recommended oil and recheck the level. For crankcase capacity, see Capacities and Specifications.
Caution: Do not add too much oil. Oil levels above or below the acceptable range are harmful to the engine. Drain excess oil or seek professional service if necessary.
Selecting the Right Engine Oil
Engine oil selection depends on proper specification and viscosity grade:
- Specification: Use full synthetic engine oils that meet dexos1 specification.
- Viscosity Grade: Use SAE 0W-20 viscosity grade engine oil.
Do not add engine oil additives or use engine oil flushes, as they may cause damage not covered by warranty.
What to Do with Used Oil
Used engine oil can be hazardous to health and the environment. Clean your skin thoroughly and dispose of used oil responsibly at a collection point. Never pour oil on the ground, into sewers, or in trash.
Engine Oil Life System
This vehicle has a computer system that indicates when to change engine oil and filter based on engine revolutions, temperature, and miles driven.
Reset the system every time the oil is changed. If reset accidentally, oil must be changed after 5,000 km (3,000 mi) since the last oil change.
How to Reset the Engine Oil Life System
- Display OIL LIFE on the vehicle information screen.
- Touch RESET to clear the CHANGE ENGINE OIL SOON message and reset oil life to 100%.
Alternatively:
- Display OIL LIFE.
- Fully press and release the accelerator pedal three times within five seconds. If the CHANGE ENGINE OIL SOON message is off, the system is reset.
Automatic Transmission Fluid
If diesel engine, see Duramax supplement. Normally, checking is unnecessary. Fluid loss only occurs from leaks or overheating. No dipstick is present; check and change procedure is dealer-only. Always use correct fluid per Recommended Fluids and Lubricants. Change fluid and filter per Maintenance Schedule.
Engine Air Filter Life System
If equipped, this shows the remaining life of the engine air filter and best timing for replacement. Reset system after changing filter.
How to Reset the Engine Air Filter Life System
- Place vehicle in P (Park).
- Access Air Filter Life screen from Vehicle Information.
- Touch Reset, then Yes to confirm.
Engine Air Cleaner/Filter
If diesel engine, see Duramax supplement. Located on the driver side of engine compartment. Inspect/replace per Maintenance Schedule.
Warning: Do not start engine with air cleaner/filter off. Replace with same part number. Operating engine without filter can cause burns or damage.
Caution: Dirt can enter engine if air cleaner/filter is off. Always have filter in place when driving.
Cooling System
For Duramax diesel, see supplement. Maintains correct engine temperature.
- Engine Electric Cooling Fans (Out of View)
- Coolant Surge Tank and Pressure Cap
Warning: Electric fans may start even when engine is off. Keep hands, clothing, and tools away. Do not touch hot engine parts or run engine if coolant is leaking. Fix leaks before driving.
Engine Coolant
System filled with DEX-COOL coolant, lasts 5 years or 240,000 km (150,000 mi). Use a 50/50 mixture of clean, drinkable water and DEX-COOL coolant:
- Freezing protection down to −37 °C (−34 °F)
- Boiling protection up to 129 °C (265 °F)
- Protects against rust and corrosion
- Will not damage aluminum parts
Caution: Do not use liquids other than DEX-COOL + water. Dispose of coolant properly; never pour on ground or in water.
Checking Coolant
The coolant surge tank is in the engine compartment on the driver side. The vehicle must be on level ground when checking coolant level.
