2012 Isuzu N-Series

The Office of Defects Investigations (ODI) opened this Preliminary Evaluation (PE) investigation on September 28th 2015 to investigate field reports submitted by Isuzu during quarterly Early Warning Reporting (EWR) describing wheel bearing failure(s) on model year (MY) 2012-2015 N-Series trucks.In addition an ODI investigator interviewed Isuzu automotive technicians to better understand the impact of this alleged failure mechanism.Isuzu technicians indicated subject Isuzu trucks had been brought in with bearings showing signs of excessive heat. On December 18th 2015 ODI received a response from Isuzu to an Information Request (IR) letter sent to them by the agency.Isuzu indicated that while they have an elevated warranty rate on certain model vehicles, there are no consumer complaints, injuries, crashes, property damage, fires or wheel off events related to bearing failures.In the worst case Isuzu explained that drivers were able to reach the roadside or other locations of safety when a bearing failure occurred.Conditions where wheel bearing has seized, the vehicle(s) could continue to be driven for a number of miles, producing a loud noise while the ABS warning light illuminates.Isuzu is aware of the elevated warranty numbers for certain model and MY vehicles and will issue an extended warranty for the subject population and further expand the scope to 2016 vehicles.Walk in van (MY 2012-2016) and diesel 14.5K truck (MY 2011-2016) owners will receive letters informing them that Isuzu is conducting a service campaign for the front wheel bearing assemblies.Customers with 60,000 miles or less on their vehicle should bring their vehicle to their dealer. Isuzu dealers will replace the grease and conduct an inspection of the wheel bearings at no charge. Additionally, Isuzu will replace wheel bearings, if necessary.Customers with over 60,000 miles should contact their dealers to schedule an appointment if they have not already had the wheel bearing grease replaced in the past. These vehicles will be handled on a case-by-case basis.Isuzu will send a letter to all customers and dealers to remind them of the required maintenance schedule for the wheel bearing grease of 30,000 miles or 24 months for all MY 2011-2016 N-Series vehicles and recommend that customers use the manufacturer specified grease during maintenance.ODI's analysis indicates that the warranty rate for wheel bearing failure is less than 1% for a population of vehicles with up to four years in service.There are no known crashes or injuries and Isuzu's extended warranty campaign addresses the issues identified in this investigation.In view of the foregoing, this investigation is closed.The closing of this investigation does not constitute a finding by NHTSA that no safety-related defect exists.The agency will take further action if warranted by the circumstances.

INFORMATION BULLETIN: THE INFORMATION SET FORTH IN THIS BULLETIN IS INTENDED TO AID TECHNICIANS IN PROPERLY TESTING THE BATTERIES AND ALTERNATORS IN THE AFFECTED ISUZU VEHICLES. IT IS IMPORTANT TO CONFIRM THE BATTERY IS IN GOOD CONDITION PRIOR TO DIAGNOSIS OF THE ALTERNATOR AND CHARGING SYSTEM. NEVER REPLACE AN ALTERNATOR BEFORE TESTING THE BATTERY’S CONDITION.

SERVICE BULLETIN - THE PURPOSE OF THIS BULLETIN IS TO DESCRIBE DIFFERENT INSTANCES WHERE OIL CONSUMPTION OCCURS AND TO MAKE AVAILABLE A WORKSHEET TO ASSIST THE TECHNICIAN IN DETERMINING IF OIL CONSUMPTION IS EXCESSIVE. OIL USAGE HAS A DIRECT RELATIONSHIP WITH THE AMOUNT OF FUEL USED. THE HARDER AN ENGINE WORKS, THE MORE FUEL AND OIL IT WILL USE. THEREFORE, OIL USAGE AS A FACTOR OF FUEL USAGE IS A MORE ACCURATE INDICATOR OF ACCEPTABLE OIL CONSUMPTION. THE ACCEPTED RATE OF OIL CONSUMPTION FOR THE AFFECTED VEHICLES IN THIS BULLETIN IS 0.946 LITER (1 QT) WITHIN 379 LITERS (100 GALLONS) OF FUEL USED. THIS RATE ONLY APPLIES TO VEHICLES UNDER WARRANTY, MAINTAINED IN ACCORDANCE WITH THE APPROPRIATE MAINTENANCE SCHEDULE, DRIVEN AT LEGAL SPEEDS AND WITHIN DESIGN INTENT OF THE VEHICLE. MANY FACTORS CAN AFFECT AN OWNER'S CONCERN WITH OIL CONSUMPTION. DRIVING HABITS AND VEHICLE MAINTENANCE VARY FROM OWNER TO OWNER. THOROUGHLY EVALUATE EACH CASE BEFORE DECIDING WHETHER THE VEHICLE IN QUESTION HAS ABNORMAL ENGINE OIL CONSUMPTION.

INFORMATION BULLETIN: SOME CUSTOMERS WITH N-SERIES VEHICLES MAY NOTICE AN AUDIBLE CLICKING OR CHATTERING NOISE COMING FROM THE REAR OF THE VEHICLE WHILE MAKING TIGHT TURNS. THIS CONDITION MAY BE DUE TO LIMITED SLIP DIFFERENTIAL LUBRICANT ADDITIVE NOT HAVING BEEN USED DURING THE LAST SCHEDULED MAINTENANCE OR IN A PREVIOUS REPAIR. THE CONDITION CAN ALSO RESULT FROM DELAYED OR SKIPPED MAINTENANCE RESULTING IN DEGRADATION OF AXLE FLUID. IF A CUSTOMER BRINGS AN AFFECTED VEHICLE IN AND COMPLAINS OF OR DESCRIBES THIS CONDITION, FOLLOW THE SERVICE PROCEDURE.

INFORMATION BULLETIN: CLEAN IDLE LABEL REPLACEMENT PROCEDURES

INFORMATION BULLETIN: THE VACUUM PUMP SERVICE PART FOR AFFECTED VEHICLES LISTED IN THIS BULLETIN HAS BEEN SUPERSEDED AND IS NOW THE SAME VACUUM PUMP THAT IS THE SERVICE PART FOR THE 6.6L GAS ENGINE. THE UPDATED PUMP REQUIRES THE OUTLET VACUUM HOSE TO BE REROUTED FOR PROPER FITMENT. FOLLOW THE SERVICE PROCEDURE BELOW TO INSTALL THE UPDATED REPLACEMENT VACUUM PUMP AND REROUTE THE OUTLET VACUUM HOSE AS SET FORTH BELOW.

INFORMATION BULLETIN: THE INFORMATION SET FORTH IN THIS BULLETIN IS INTENDED TO AID TECHNICIANS IN PROPERLY TESTING THE BATTERIES AND ALTERNATORS IN THE AFFECTED ISUZU VEHICLES. IT IS IMPORTANT TO CONFIRM THE BATTERY IS IN GOOD CONDITION PRIOR TO DIAGNOSIS OF THE ALTERNATOR AND CHARGING SYSTEM. NEVER REPLACE AN ALTERNATOR BEFORE TESTING THE BATTERY’S CONDITION. BATTERIES MUST BE FULLY CHARGED FOR THE ECM AND/OR STARTER RELAY TO FULLY ENGAGE WITH THE STARTER. IF THE BATTERY VOLTAGE IS LOW, THE ECM WILL NOT ENGAGE OR MAY PARTIALLY ENGAGE THE STARTER. REPLACE THE ALTERNATOR ONLY IF IT FAILS THE ON VEHICLE TESTING PROCEDURE.