Engine - Oil Level and Grade, Driveability

Classification:
EM95-01

Section:
Engine Mechanical

Reference:
Technical Bulletin NTB95-017

Date:
February 8, 1995

ENGINE OIL LEVEL AND GRADE

APPLIED VEHICLES:
All

SERVICE INFORMATION

The cause of some driveability incidents is incorrect oil level or viscosity. Whenever you evaluate a vehicle for a driveability problem, check the oil level first. (It is a good practice to check oil level on
every vehicle that you work on.)

Overfilling may cause engine vibration or valve train clatter on vehicles with hydraulic lash adjusters due to oil aeration when the crankshaft hits the oil. Using the wrong viscosity oil can cause rough or low idle resulting from improper operation of the hydraulic lash adjusters.

When you add or change the engine oil, follow the service manual recommendations regarding proper oil fill level. Do not overfill the crankcase. If you find a vehicle to be overfilled with oil, drain the excess oil and dispose of properly. Remember to wait ten (10) minutes after refilling before checking. This allows time for the oil to drain back to the pan.

Always use the proper viscosity oil specified by the service manual for the temperature range in your geographic area. The viscosity specifications ensure proper engine operation and best engine efficiency.