GM Service Manual Online
For 1990-2009 cars only

For diesel engine vehicles, see "Engine Oil" in the DURAMAX® Diesel manual.

Checking Engine Oil

It is a good idea to check the engine oil level at each fuel fill. In order to get an accurate reading, the oil must be warm and the vehicle must be on level ground.

The engine oil dipstick handle is a yellow loop. See Engine Compartment Overview for the location of the engine oil dipstick.

  1. Turn off the engine and give the oil several minutes to drain back into the oil pan. If this is not done, the oil dipstick might not show the actual level.
  2. Pull out the dipstick and clean it with a paper towel or cloth, then push it back in all the way. Remove it again, keeping the tip down, and check the level.

When to Add Engine Oil


Object Number: 869560  Size: B1

If the oil is below the cross-hatched area at the tip of the dipstick, add at least one quart/liter of the recommended oil. This section explains what kind of oil to use. For engine oil crankcase capacity, see Capacities and Specifications.

Notice: Do not add too much oil. If the engine has so much oil that the oil level gets above the cross-hatched area that shows the proper operating range, the engine could be damaged.


Object Number: 824596  Size: A2

See Engine Compartment Overview for the location of the engine oil fill cap.

Add enough oil to put the level somewhere in the proper operating range. Push the dipstick all the way back in when through.

What Kind of Engine Oil to Use

Look for three things:


Object Number: 1501606  Size: B4
    • GM6094M
        Use only an oil that meets GM Standard GM6094M.
    • SAE 5W-30
        SAE 5W-30 is best for the vehicle. These numbers on an oil container show its viscosity, or thickness. Do not use other viscosity oils such as SAE 20W-50.
    • American Petroleum Institute (API) starburst symbol

Object Number: 808500  Size: A2

Oils meeting these requirements should have the starburst symbol on the container. This symbol indicates that the oil has been certified by the American Petroleum Institute (API).

Notice: Use only engine oil identified as meeting GM Standard GM6094M and showing the American Petroleum Institute Certified For Gasoline Engines starburst symbol. Failure to use the recommended oil can result in engine damage not covered by the vehicle warranty.

Cold Temperature Operation

If in an area of extreme cold, where the temperature falls below -20°F (-29°C), use either an SAE 5W-30 synthetic oil or an SAE 0W-30 engine oil. Both provide easier cold starting for the engine at extremely low temperatures. Always use an oil that meets the required specification, GM6094M. See "What Kind of Engine Oil to Use" for more information.

Engine Oil Additives / Engine Oil Flushes

Do not add anything to the oil. The recommended oils with the starburst symbol that meet GM Standard GM6094M are all that is needed for good performance and engine protection.

Engine oil system flushes are not recommended and could cause engine damage not covered by the vehicle warranty.

Checking Engine Oil

It is a good idea to check the engine oil level at each fuel fill.

The engine oil dipstick handle is a yellow loop. See Engine Compartment Overview for the location of the engine oil dipstick.

In order to get an accurate reading, the oil must be warm, at normal operating temperature, and the vehicle must be on level ground.

  1. Turn off the engine and give the oil at least five minutes to drain back into the oil pan. With a cool engine, allow 30 minutes. If this is not done, the oil dipstick might not show the actual level.
  2. Pull out the dipstick and clean it with a paper towel or a cloth, then push it back in all the way. Remove it again, keeping the tip down.

Object Number: 1817588  Size: B1

When to Add Engine Oil

If the oil is below the add mark (A) at the tip of the dipstick, add at least one quart/liter of the recommended oil. This section explains what kind of oil to use. For engine oil crankcase capacity, see Specification Charts.

Notice: Do not add too much oil. If the engine has so much oil that the oil level gets above the full mark (F) on the dipstick, the engine could be damaged.


Object Number: 1284396  Size: A2

See Engine Compartment Overview for the location of the engine oil fill cap.

Be sure to add enough oil to put the level somewhere in the proper operating range. Push the dipstick all the way back in when through.

What Kind of Engine Oil to Use

Look for three things:


Object Number: 1802972  Size: B5
    • CJ-4
        Oils designated as API CJ-4 are required for the vehicle. The CJ-4 designation can appear either alone or in combination with other American Petroleum Institute (API) designations, such as API CJ-4/SL. These letters show API levels of quality.
    • SAE 15W-40
        SAE 15W-40 is best for the vehicle. When it is very cold, below 0°F (-18°C), use SAE 5W-40 to improve cold starting. These numbers on the oil container show its viscosity, or thickness. Do not use other viscosity oils such as SAE 10W-30, SAE 10W-40, or SAE 20W-50.
    • American Petroleum Institute (API) symbol

Object Number: 1803035  Size: A2

This doughnut-shaped logo (symbol) is used on most oil containers to help you select the correct oil. It means that the oil has been certified by the American Petroleum Institute.

    • Look for this on the oil container, and use only those oils that display this logo.

Notice: Use only engine oils that have the designation CJ-4 for the diesel engine. Failure to use the recommended oil can result in engine damage not covered by the vehicle warranty.

Engine Oil Additives / Engine Oil Flushes

Do not add anything to the oil. The recommended oils with the API service symbol are all that is needed for good performance and engine protection.

Engine oil system flushes are not recommended and could cause engine damage not covered by the vehicle warranty.