Date: Feb. 18, 2000
models: 1999 - 2000 (BR/BE) Ram Truck
NOTE. THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH A 5.9L DIESEL ENGINE.
Discussion:
A customer may complain of a heavy oil or fuel-like odor coming from the engine compartment. This condition may occur after the engine oil has been changed. The odor appears to reduce in intensity as the engine oil ages. This aging usually occurs between the first 300 to 500 miles following the oil change.
NOTE: DO NOT CONFUSE THE HEAVY OIL OR FUEL-LIKE ODOR WITH A DIESEL ENGINE EXHAUST ODOR.
The odor condition is the result of certain diesel engine oil additives. These oil additives are blended with the base oil during the manufacture of the engine oil. Some diesel engine oils with the American Petroleum Institute quality rating of CH-4 or CH-4+ may be more prone to exhibiting the odor condition.
NOTE: THE DAIMLERCHRYSLER RECOMMENDED DIESEL ENGINE OIL, P/N 04798231 (QT.) OR P/N 0479832 (GAL.), IS FORMULATED TO MINIMIZE THE HEAVY OIL ODOR CONDITION.
To possibly reduce the further incidence'of the odor condition, the integrity of the cowl seal should be verified. The cowl seal is located between the rear edge of the hood and the cowl panel. Diesel engine oil vapors, which develop during normal engine operation, exit the engine through the engine road draft tube. The heavy oil or fuel-like odor may leak past an opening in the cowl seal and enter the passenger compartment through the HVAC system. This may occur more frequently if the vehicle is at a stop, with the engine running, and the HVAC system is being operated in any mode other than "Re-circulate".
NOTE: ANY OPENING OR VOIDS IN THE COWL SEAL SHOULD BE CORRECTED. VERIFY THAT FULL CONTACT BETWEEN THE HOOD AND COWL SEAL IS PRESENT ALONG THE ENTIRE LENGTH OF THE SEALING SURFACES. PAY PARTICULAR ATTENTION TO THE SEALING INTEGRITY AT BOTH ENDS OF THE COWL SEAL.
Notes:
POLICY. Information Only