Information on Over-Filling Dry Sump Oiling System and Maintaining Proper Oil Level on LS7 Engine

This bulletin is being revised to add 2008 model year and add information on checking Z06 engine oil. Please discard Corporate Bulletin Number 05-06-01-032A (Section 06 - Engine).

The 2006 through 2008 Chevrolet Corvette Z06 is equipped with a dry sump engine oiling system. When adding engine oil to the LS7 dry sump oiling system, care must be taken to avoid overfilling the system.

Caution: Overfilling may cause over-pressurization to the system which may result in damage to the engine and emissions system components.

The capacity for the LS7 oil fill (with filter) is 7.6L (8 qts). When checking the Z06 engine oil level, follow the service instructions in this bulletin. However, if the amount of engine oil in the system is unknown due to repairs or other causes, the entire system should be drained and refilled with the correct amount of engine oil.

Checking Z06 Engine Oil

1. Engine Oil Level Indicator
2. Engine Oil Fill Cap

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

The engine oil level indicator handle is a yellow loop. The level indicator is located on the dry sump engine oil tank. The location of the dry sump engine oil tank is on the passenger side of the vehicle.

Z06 models have a dry sump engine lubrication system. This high-performance system operates differently than a standard engine lubrication system and requires a special procedure when checking the engine oil level. Follow this procedure closely when checking the engine oil level.

The engine oil level must be checked when the engine is warm. Cold oil level in the dry sump tank may not indicate the actual amount of oil in the system. With this system, engine oil is contained in an external tank, separate from the engine.

Under normal operating conditions, the oil pan under the engine does not store any oil. If the vehicle has been parked for an extended period without the engine being started, some oil will seep back into the oil pan, reducing the amount of oil held in the dry sump tank and there could be no engine oil at all showing on the level indicator.

This is normal since the level indicator is designed to read engine oil level only after the engine has run long enough to reach normal operating temperature. Do not add engine oil based on cold engine level indicator readings. The engine oil level on the level indicator will also be inaccurate if checked while the engine is running.

1. To obtain an accurate engine oil level reading, warm up the engine to at least 175°F (80°C). Cold oil will not give a correct oil level reading.
2. Once the engine is warm, turn off the engine. Checking the oil while the engine is running will result in an incorrect oil level reading.
3. Wait at least five minutes (but not more than 20 minutes) to allow oil to drain and settle in the engine.
4. Remove the level indicator from the external engine oil tank and clean it with a lint-free paper towel or a cloth. Re-insert the level indicator into the external oil tank, pushing it all the way in until it stops.
5. Remove the level indicator from the oil tank and read the level on the cross-hatched area. Oil levels that fall in the cross-hatched area are normal.