2017 Peterbilt 389

The Office of Defects Investigation (ODI) opened this Preliminary Evaluation (PE21-015) based on one Vehicle Owner Questionnaire (VOQ) and supporting fleet reports. The reports indicated that the subject quarter fenders were prone to cracking and/or separation.After a comprehensive review of the data related to the quarter fender failures on the subject vehicles, ODI did not identify the existence of a safety-related defect trend. Quarter fender failures resulted in a warranty claim rate less than one percent (<1%) of the total vehicle population. All separations, including those due to tread separations, road hazards, etc., accounted for less than point one percent (<0.1%) of the total vehicle population.ODI discovered that the minimum recommended gap between the top of the quarter fender and the bottom of the trailer was not known or being followed. The optional quarter fenders were supplied by Fontaine Spray Systems (FSS), who recommended a two inch (2) gap. ODI analyzed the claim data using a calculated gap. A calculated gap using the top of the quarter fender flap and assuming the trailer is level with the top of the fifth wheel hitch was necessary, as PACCAR doesn't know specifically what trailer a purchaser will couple to the tractor. It is safe to assume no trailers on the market extend below the upper fifth wheel plate, but many do provide additional clearance over the wheels where the quarter fenders are located. ODI determined that 94 percent of warranty claims and 84 percent of separations violated FSS' recommendation.ODI confirmed that the VOQ vehicle and the fleet report vehicles also violated FSS' recommended gap. In one fleet the gap was negative point three inches (-0.3).PACCAR has updated its vehicle specification process and issued a customer advisory notice to existing owners. In light of the low rate of reported failures and separations, further use of agency resources does not appear to be warranted. The closing of this investigation does not constitute a finding by NHTSA that no safety-related defect exists. The agency reserves the right to take further action if warranted by the circumstances.

On May 1, 2020, the Office of Defects Investigation (ODI) opened PE20006 to investigate complaints of intermittent loss of power steering assist in Daimler Truck North America (DTNA), Volvo Trucks of North America (Volvo) and PACCAR vehicles equipped with a ZF/TRW (TRW) THP60 steering gear.  The investigation focused on 2010-2020 DTNA Freightliner Cascadia, M2 and WST; Volvo VN, VAH and VHD and PACCAR 337, 365, 389, 567, 579 model vehicles.Field reports and interviews with fleet drivers allege that high power steering fluid temperatures could result in internal seal and bearing failures causing pressure fluctuation, affecting left and right-hand turns.  The inability of the driver to steer the vehicle as intended can increase the risk of a crash and injury. ODI analyzed data provided by TRW, DTNA, Volvo, and PACCAR in response to individual information request letters.ODI found that most failures occurred within the first two years and/or 50,000 miles of service.  The claim rate decreased with time and miles in service and remained less than 0.5%. ODI normalized data from each of the manufacturers and determined that there was not a substantial difference in the failures.Additionally, TRW improved a seal in the steering gear in December 2015.Trucks built on or after 2016 (as 2017 and newer model years) show a decreasing trend of failures. In view of the overall low failure rate, the nature of early-life failure, and failure rate trending downward for model years 2017 and newer, this Preliminary Evaluation (PE) is closed.  The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist.The Agency reserves the right to take additional action if warranted by future circumstances. To review the ODI reports cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.

HEAT FROM THE NEW DEF REQUIREMENTS ARE CAUSING PROBLEMS. THE HEAT OFF OF THE DEF SYSTEM STAYS TRAPPED UNDER THE VEHICLE. WHICH IS CAUSING EARLY WEAR ON ELECTRICAL HARNESSES ALONG WITH AXLE SEALS. I'VE REPLACED 3 WHEEL SEALS AND 2 FRONT DIFFERENTIAL SEALS. THE DEF HARNESS HAS FAILED TWICE NOW. PLEASE LOOK INTO THIS. THE HEAT STAYS UNDER THESE VEHICLES. AND THE MANUFACTURER WILL NOT ACCEPT RESPONSIBILITY FOR THIS. *DT*JB

NHTSA ID

11181438

Incident

Feb 8, 2019

Mileage

20,000 mi

105 chassis have been removed from the chassis list and unflagged in PRWS due to expiration of applicable warranty coverage. Total chassis population is 732.

The Condition, Chassis Affected, Service Action, Warranty, and Procedure sections have been updated to include the latest prognostics bulletin verbiage.

The attached procedures document has been updated with more detail and explanations. This is not a stand-alone procedure. Cummins Quickserve troubleshooting will specify the use of these procedures while troubleshooting specific fault codes.

EPA17-24 MX Fuel Injector Connector - This bulletin has been revised to include all EPA17-24 and CARB24 PACCAR MX engines.

Procedure pictures updated for clarity. When troubleshooting Cummins X15 fault codes 555 or 556, follow this additional testing, inspection, and documentation procedure to help identify the root cause of dusted engines. This is not a stand-alone process but must be used alongside Cummins troubleshooting steps. Cummins Quickserve will reference this bulletin for fault codes 555 or 556.

T016: Warranty section updated to include 0.5 hours for test drive. Recommended Repair T016C has been updated from 6.4 hours to 6.9 hours. SRT codes updated in PRWS Claim Coding Table: B25-17A for 6.9 hours created to replace all other codes. 26-040: Warranty section updated to include 0.5 hours for test drive. Recommended Repair 26040C has been updated from 6.4 hours to 6.9 hours. SRT codes updated in PRWS Claim Coding Table: B25-17A for 6.9 hours created to replace all other codes.