No complaints are listed for the 2021 MCI D4520. NHTSA's API and bulk file list none in this build.
Data build 2026-10-09.
NHTSA lists this vehicle as MCI D4520.
Model-generated complaint tags: No complaints are listed for tagging.
Recalls
See new recalls and investigations this week.
1 recalls.
Date: 2021-12-15. Systems: FUEL SYSTEM, DIESEL.
Defect: Motor Coach Industries (MCI) is recalling certain 2019-2022 D4000 ISTV, D4500, 2021 D4000, D4520, 2020-2021 D4505, D4005, 2020-2022 D45CRTLE, and 2019-2021 J4500 vehicles equipped with certain Cummins X12 diesel engines. The fuel tubes between the fuel rail and the injectors for cylinders four, five, and six may fatigue and crack, which can result in a high pressure fuel leak.
Consequence: A high pressure fuel leak in the presence of an ignition source can increase the risk of a fire.
Remedy: On engines with 75 miles or less, Cummins dealers will install vibration isolators to the fuel tubes. Engines with more than 75 miles will receive new fuel tubes with vibration isolators. Repairs will be performed free of charge. Owner notification letters were mailed March 11, 2022. Owners may contact MCI customer service at 1-800-241-2947. MCI's number for this recall is R21-028.
Do not drive: No. Park outside: No.
Manufacturer communications
11 manufacturer communications.
Communications by system| System | Count |
|---|
| STRUCTURE | 3 |
|---|
| ELECTRICAL SYSTEM | 2 |
|---|
| ENGINE | 2 |
|---|
| FUEL SYSTEM, DIESEL | 2 |
|---|
| ENGINE AND ENGINE COOLING | 1 |
|---|
| LATCHES/LOCKS/LINKAGES | 1 |
|---|
| SERVICE BRAKES | 1 |
|---|
| SERVICE BRAKES, HYDRAULIC | 1 |
|---|
11036144
Date: 2026-08-11. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM, SERVICE BRAKES.
This bulletin is to provide instructions for clearing DTC 1067 FMI 7 (Pressure Sensor Not Calibrated) and FMI 11 (Primary and Secondary Circuit Pressure Sensor (PS1/PS2) Plausibility Error - BS Pressure), when required to prevent the loss of Adaptive Cruise Control functionality and the illuminatio
11034101
Date: 2026-06-11. Type: Service Bulletin/Repair Instructions. Systems: ENGINE.
This bulletin introduces an optional product improvement to the A/C compressor drive system for coaches equipped with a Cummins X12. The improved pulley system is available for customers who wish to reduce noise and vibration characteristics and may be installed at the customera s discretion.
11032280
Date: 2026-05-06. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM.
This TSIB provides information to provide a software update. Some coaches using MCC HVAC Eco-Tempo ECU # 07-10-009 software T35-1581 / V1.04 may be experiencing random fault codes due to MCC software errors.
11029031
Date: 2026-02-09. Type: Service Bulletin/Repair Instructions. Systems: STEERING, SUSPENSION.
This TSIB is to inform customers the recommended steering axle cleaning/greasing instructions to prevent damage on axle components due to displacement of grease from the bearings, lubrication reduction and accelerate wear for coaches with independent front suspension.
11011092
Date: 2024-11-05. Type: Service Bulletin/Repair Instructions. Systems: ENGINE, UNKNOWN OR OTHER.
Information to owners showing the proper procedure for checking the oil level in a BITZER HVAC compressor.
11005621
Date: 2024-07-17. Type: Service Bulletin/Repair Instructions. Systems: STRUCTURE.
Service instruction for updating plug doors to improve reliability and reduce wind noise.
10232558
Date: 2023-02-10. Type: Service Bulletin/Repair Instructions. Systems: LATCHES/LOCKS/LINKAGES, STRUCTURE.
Instructions to properly adjust entrance door to ensure proper operation.
10232557
Date: 2023-02-02. Type: Service Bulletin/Repair Instructions. Systems: FUEL SYSTEM, DIESEL.
Instructions for improving fuel tank venting while fueling.
10213037
Date: 2022-05-03. Type: Service Bulletin/Repair Instructions. Systems: STRUCTURE.
Technical Service Information Bulletin describing the retrofit for the front junction box cover on specifically equipped buses.
10210903
Date: 2022-04-01. Type: Service Bulletin/Repair Instructions. Systems: ENGINE AND ENGINE COOLING, FUEL SYSTEM, DIESEL.
This Technical Service Information Bulletin is a supplemental reminder to all MCI owners/operators of vehicles which are affected by the Cummins Equipment Recall 21E-099 and MCI Vehicle recall 21V-971.