No complaints are listed for the 2027 Mack Pioneer PR (4). NHTSA's API and bulk file list none in this build.
Data build 2026-10-09.
NHTSA lists this vehicle as MACK PIONEER PR (4).
Model-generated complaint tags: No complaints are listed for tagging.
Recalls
See new recalls and investigations this week.
6 recalls.
Date: 2026-10-01. Systems: STRUCTURE.
Defect: Mack Trucks, Inc. (Mack) is recalling certain 2026-2027 Anthem AN (4) and 2025-2027 Pioneer PR (4) vehicles. The intake and grille bezels may detach from the vehicle. (excerpt)
Consequence: A detached bezel can become a road hazard for other vehicles, increasing the risk of a crash. (excerpt)
Remedy: Dealers will inspect, replace the intake and grille bezels, and install cable ties as necessary, free of charge. Owner notification letters are expected to be mailed November 30, 2026. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0501. Vehicle Identification Numbers (VINs) involved in this recall will become searchable on NHTSA.gov on October 8, (excerpt)
Do not drive: No. Park outside: No.
Date: 2026-09-28. Systems: SERVICE BRAKES, ELECTRIC.
Defect: Mack Trucks, Inc. (Mack) is recalling certain 2026-2027 Anthem AN (4) and Pioneer PR (4) vehicles equipped with a tanker application package. Inaccurate axle load calculations may cause reduced braking performance while transporting smoothbore tanker trailers.
Consequence: Reduced braking performance can require a greater distance to stop, increasing the risk of a crash.
Remedy: Dealers will install new software to disable the dynamic trailer braking calculations, free of charge. Owner notification letters are expected to be mailed November 27, 2026. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0500. Vehicle Identification Numbers (VINs) involved in this recall will become searchable on NHTSA.gov on October 5, 2026.
Do not drive: No. Park outside: No.
Date: 2026-08-06. Systems: EXTERIOR LIGHTING.
Defect: Mack Trucks, Inc. (Mack) is recalling certain 2027 Anthem AN (4) and Pioneer PR (4) vehicles. The center roof marker lights may fail to illuminate. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, "Lamps, Reflective Devices, and Associated Equipment." (excerpt)
Consequence: Marker lights that fail to illuminate can reduce visibility, increasing the risk of a crash. (excerpt)
Remedy: Dealers will replace the center roof marker light, free of charge. Interim letters notifying owners of the safety risk were mailed September 22, 2026. Additional letters will be sent once the final remedy is available. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0498. Vehicle Iden (excerpt)
Do not drive: No. Park outside: No.
Date: 2026-05-28. Systems: WHEELS.
Defect: Mack Trucks, Inc. (Mack) is recalling certain 2026 Anthem (AN), 2026-2027 Pioneer PR (4), Pinnacle (PI/PN), Granite (GR), and 2027 Anthem AN (4) vehicles. The wheel lug nuts may loosen and allow the wheel to detach. (excerpt)
Consequence: Wheel detachment can cause a loss of vehicle control or create a road hazard, increasing the risk of a crash or injury. (excerpt)
Remedy: Owners are advised not to drive their vehicles until the repair has been performed. Dealers will inspect the wheel and hub mating surfaces, remove any masking material, and replace any worn components if necessary, free of charge. Owner notification letters were mailed June 22, 2026. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0495. Vehicle Iden (excerpt)
Do not drive: Yes. Park outside: No.
Date: 2026-04-23. Systems: SERVICE BRAKES, AIR.
Defect: Mack Trucks, Inc. (Mack) is recalling certain 2025-2027 Pioneer (4) and 2026-2027 Anthem (4) vehicles. The rear brake modulators may have unprotected electrical connectors that can short circuit and lead to a loss of the anti-lock brake system (ABS) and electronic stability control (ESC). (excerpt)
Consequence: A loss of anti-lock brakes and electronic stability control increases the risk of a crash or injury. (excerpt)
Remedy: Dealers will inspect the rear brake modulator electrical connectors, install a protective cover, and replace the rear brake modulators, as necessary, free of charge. Owner notification letters were mailed June 8, 2026. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0494. Vehicle Identification Numbers (VINs) involved in this recall will be searchab (excerpt)
Do not drive: No. Park outside: No.
Date: 2026-04-01. Systems: EXTERIOR LIGHTING.
Defect: Mack Trucks, Inc. (Mack) is recalling certain 2025-2027 Pioneer (4) and 2027 Anthem (4) trailers. The trailer turn signals may not function properly. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, "Lamps, Reflective Devices, and Associated Equipment."
Consequence: Turn signals that do not function properly may fail to indicate the driver's intention to change vehicle direction, increasing the risk of a crash.
Remedy: Dealers will update the turn signal indicator software, free of charge. Owner notification letters were mailed May 7, 2026. Owners may contact Mack's customer service at 1-800-866-1177. Mack's number for this recall is SC0493. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov April 1, 2026.
Do not drive: No. Park outside: No.
Manufacturer communications
42 manufacturer communications.
Communications by system| System | Count |
|---|
| ELECTRICAL SYSTEM | 30 |
|---|
| ENGINE | 5 |
|---|
| UNKNOWN OR OTHER | 5 |
|---|
| POWER TRAIN | 3 |
|---|
| SERVICE BRAKES | 3 |
|---|
| SEAT BELTS | 2 |
|---|
| STRUCTURE | 2 |
|---|
| WHEELS | 2 |
|---|
11037728
Date: 2026-09-27. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM.
Power Cable Alternator Replacement
11037725
Date: 2026-09-24. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM.
Instrument Cluster Going Dark
11037668
Date: 2026-09-17. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM.
Diagnostic instructions for CAN network communication issues.
11037724
Date: 2026-09-08. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM.
The purpose of this CBR is outline the interim software solution for PR(4) and AN(4).
11037821
Date: 2026-09-01. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM.
Jumper Harness Repair for Version 4 Mack Trucks
11036590
Date: 2026-08-26. Type: Service Bulletin/Repair Instructions. Systems: ENGINE.
Loose CCV mounting bolts and oil leak at CCV due to cracking of the housing. Mounting hardware found to be under-torqued after the vehicle was delivered.
11036589
Date: 2026-08-25. Type: Service Bulletin/Repair Instructions. Systems: SERVICE BRAKES.
The purpose of this CBR is to provide support for complaints of trailer braking aggressively.
11036588
Date: 2026-08-24. Type: Service Bulletin/Repair Instructions. Systems: FUEL/PROPULSION SYSTEM.
The purpose of this CBR is to provide steps on how to utilize the injector widget (within workshop toolbox) to aid with injection system issues.
11036586
Date: 2026-08-17. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM, UNKNOWN OR OTHER.
The purpose of this CBR is to provide steps on how to correct a customer complaint of "Service Required" message for air filter replacement appears in the cluster. There may be no option in PTT or the cluster to reset the air filter service interval.
11036583
Date: 2026-08-10. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM, STRUCTURE.
This CBR solution outlines the procedures for diagnosing, replacing, calibrating, and programming Flexible Switch Panels and the Security and Cab Interface Module (SCIM) to resolve switch malfunction notifications and associated fault codes.