AI Damage2021 Paccar MX-11: common problems
The maker issued 15 service bulletins for this year. Details by component below, with sources.
Key figures
- Technical service bulletins (TSB)
- 15
Components owners complain about
| Component | Owner complaints | involving a crash | Technical service bulletins (TSB) |
|---|---|---|---|
| Engine | 0 | 0 | 6 |
| Engine and cooling | 0 | 0 | 5 |
| Electrical system | 0 | 0 | 3 |
| Powertrain | 0 | 0 | 3 |
| Fuel/propulsion system | 0 | 0 | 2 |
| Fuel system | 0 | 0 | 2 |
Comparison
What to check before buying
- Engine. Cold start, unusual noises, oil leaks and engine codes.
- Engine and cooling. Radiator and fan after a frontal hit, coolant level and condition, overheating.
- Electrical system. Scan all modules, test the battery and alternator, inspect connectors near the impact zone.
- Powertrain. Shift quality under load, harsh shifts, transmission codes, CV joints.
Manufacturer service bulletins
Bulletin titles as filed with NHTSA.
- "Kenworth
Dealers should check the chassis list and SIR weekly for VIN changes. 2 chassis added to the chassis list. Peterbilt: Dealers should check the chassis list and SIR weekly for VIN changes. 10 chassis added to the…
- The attached procedure has been updated to improve clarity
- DPF Delta Pressure Sensor part number 2200138 for MX-11 engines has been added to this warranty policy
- A new Level 1 required MX-11 and MX-13 Oil Pressure Switch Breakout Harness is now available for order
- In an MX Engine is replaced, a TCS365 case must be opened to get a replacement engine emissions compliance…
In an MX Engine is replaced, a TCS365 case must be opened to get a replacement engine emissions compliance label and expert level rights for resetting and programming the engine control module.
- Part number 2300479 Engine Control Module has been added to the parts table for PACCAR MX-11EMY2021
Part number 2302109 Engine Control Module has been added to the parts table for PACCAR MX-11 andMX-13 EMY2023. Per Environment and Climate Change Canada (ECCC) regulations and guidance (Canadian Environmental…
- "PSB E327
PACCAR MX-11 and MX-13 OBD Software Update Vehicles equipped with PACCAR MX engines with Engine Software Version NA202 or NA206 may display a dash STOP lamp incorrectly. PCI-2 software on these chassis must be reverted…
- EPA21 Pack 2 Injectors Newly designed fuel injectors are available for EPA2021 compliant PACCAR MX-series…
EPA21 Pack 2 Injectors Newly designed fuel injectors are available for EPA2021 compliant PACCAR MX-series engines to optimize engine performance. Injectors must be replaced as a full set (6 injectors) and associated…
- Certain chassis that completed the E310 software update and received the specified in-tank additive may…
Certain chassis that completed the E310 software update and received the specified in-tank additive may require additional doses of the in-tank additive. This bulletin covers additional additive eligibility criteria…
- Info Only
LIN hybrid switch harnesses are available to order from PACCAR Parts.
- An EPA21 MX fuel injector cleaning procedure is available
The attached document details the fuel injector cleaning procedure and helps to determine when it is necessary to replace the injectors.
- Fix-As-Fail â Due to undersupply issues, only a limited supply of Diesel Exhaust Fluid (DEF) sensors are…
Fix-As-Fail â Due to undersupply issues, only a limited supply of Diesel Exhaust Fluid (DEF) sensors are available. As a temporary solution, after PACCAR confirms a DEF sensor is not available, a temporary software…
NHTSA lists 15 bulletins for this year; the 12 newest are shown here.
Other years of this model
Questions and answers
What are the most common problems with the 2021 Paccar MX-11?
There are no owner complaints in the NHTSA data for this year; the data comes from 15 manufacturer service bulletins.
How many service bulletins (TSB) were issued for the 2021 Paccar MX-11?
NHTSA lists 15 manufacturer service bulletins for this year. A bulletin tells dealers how to diagnose or fix a known issue; it is not a recall.
Should I buy a 2021 Paccar MX-11 from a US auction?
Owner complaints describe defects, not crash damage. Before bidding, check the components listed above and review the lot photos: VinWind builds a report of visible and hidden damage by VIN.
Other 2021 models
Read also
Sources: public NHTSA data (USA): service bulletins and owner complaints; YouTube: links to videos credited to their authors. Complaints are owner statements not verified by NHTSA, and describe defects rather than crash damage. Data updated 2026-11-04.