TSB: KENWORTH 389, 536, 567, 579, T280, T380, T480, T680, T880 (2021)
Bulletin 43-069 — August 17, 2021
Bulletin Details
| Bulletin ID | 43-069 |
| Manufacturer | KENWORTH |
| Models | 389, 536, 567, 579, T280, T380, T480, T680, T880 |
| Model Years | 2021 |
| Date Issued | August 17, 2021 |
| Date Added to NHTSA | September 3, 2021 |
| Component | FUEL SYSTEM, DIESEL |
| Vehicles Affected | 14 combinations |
What is a TSB?
A Technical Service Bulletin is a document issued by the vehicle manufacturer to inform dealership technicians about a known issue and the recommended repair procedure. TSBs are not mandatory recalls — they serve as repair guidance for common problems.
If your vehicle has this issue, bring this bulletin ID to your dealer. If under warranty, the repair should be covered at no cost.
Summary
A DPF regeneration two-position switch parameter is causing inhibited DPF regeneration. A parameter update, via Cummins Insite, restores proper DPF regeneration function.
Affected Vehicles
| Make | Model | Year | Component |
|---|---|---|---|
| PETERBILT | 389 | 2021 | 080000 FUEL SYSTEM, DIESEL |
| PETERBILT | 536 | 2021 | 080000 FUEL SYSTEM, DIESEL |
| PETERBILT | 567 | 2021 | 080000 FUEL SYSTEM, DIESEL |
| PETERBILT | 579 | 2021 | 080000 FUEL SYSTEM, DIESEL |
| KENWORTH | T280 | 2021 | 110000 ELECTRICAL SYSTEM |
| KENWORTH | T280 | 2021 | 350000 EQUIPMENT |
| KENWORTH | T380 | 2021 | 110000 ELECTRICAL SYSTEM |
| KENWORTH | T380 | 2021 | 350000 EQUIPMENT |
| KENWORTH | T480 | 2021 | 110000 ELECTRICAL SYSTEM |
| KENWORTH | T480 | 2021 | 350000 EQUIPMENT |
| KENWORTH | T680 | 2021 | 110000 ELECTRICAL SYSTEM |
| KENWORTH | T680 | 2021 | 350000 EQUIPMENT |
| KENWORTH | T880 | 2021 | 110000 ELECTRICAL SYSTEM |
| KENWORTH | T880 | 2021 | 350000 EQUIPMENT |
Related KENWORTH Recalls
What Should You Do?
If your vehicle is affected by this TSB, contact your authorized KENWORTH dealer. Bring this bulletin ID (43-069) when you visit. If under warranty, the repair should be free. If your warranty has expired, ask about goodwill coverage — manufacturers sometimes cover TSB-related repairs beyond the warranty period.
Frequently Asked Questions
A recall is a mandatory safety fix — the manufacturer must repair every affected vehicle for free. A TSB is an advisory document that describes a known issue and the recommended fix, but repairs are not required. However, some TSBs eventually lead to recalls if the issue poses a safety risk. TSBs are generally issued for quality or performance problems, while recalls address safety defects.
If your vehicle is still under the manufacturer's warranty, TSB-related repairs are typically covered at no cost. If your warranty has expired, you can ask the dealer about goodwill or customer assistance programs. Many manufacturers will cover or partially cover repairs for well-known issues, especially if the TSB was issued recently or affects a large number of vehicles.
Check the make, model, and model year listed above against your vehicle. If they match, this bulletin likely applies. However, TSBs may only affect vehicles with specific production dates, VIN ranges, or configurations. Your dealer can confirm by entering your VIN into their service system, which will show all applicable TSBs and recalls.
This data comes from the National Highway Traffic Safety Administration (NHTSA). Manufacturers are required to submit copies of all communications (including TSBs) sent to their dealers to NHTSA. The agency makes this data publicly available as part of its vehicle safety monitoring program.