43-089
Service Bulletin/Repair Instructions
This optional software update is expected to be available after 08/28/2026.
Vehicle report
2026 KENWORTH L770
Service bulletins
6 bulletinsTechnical service bulletins are instructions a manufacturer sent its dealers about a known fault. They are not recalls and the work is usually not free, but they are the clearest signal of a problem the manufacturer already knows about.
24KWC/24PBC
Service Bulletin/Repair Instructions
Updated Sheppard Steering Gear Classification Tool link in Inspection Procedure
99-052
Service Bulletin/Repair Instructions
There is an update to the Base Emissions Warranty Limits table [PR1.1]and general certification information in certain Engine Model Year (EMY) 2026 MX-11 and MX-13 Operator’s Manuals.
26PACA
Service Bulletin/Repair Instructions
Updated cross shaft and bearing installation steps have been added to the repair procedures.
E326
Emissions
EPA17-24 MX Fuel Injector Connector - This bulletin has been revised to include all EPA17-24 and CARB24 PACCAR MX engines.
25PACF
Service Bulletin/Repair Instructions
Parts and procedures are now available for all affected chassis equipped with Vehicle Electronic Control Unit (VECU) part number Q21-1157-013-011 / Q21-1157-013-013 / Q21-1157-002-002 / Q21-1157-004-004 / Q21-1157-006-006 / Q21-1157-009-009. See attached Parts Matrix for required parts per chassis.
Reading this report
Complaint counts are reports filed with NHTSA, not failure rates. A common model collects more of them than a rare one that breaks more often.