# Service bulletin K21052070

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

- Type: Service bulletin
- NHTSA id: 10142731
- Published by NHTSA: 2018\-07\-16
- Manufacturer's number: K21052070
- Manufacturer's date: 2018\-06\-29
- NHTSA component: FUEL SYSTEM, GASOLINE; ENGINE

## NHTSA's summary

Intermittent Occurrences Of Very Brief Loss Of Power, Engine Stumble Or Hiccup Lasting Much Less Than A Second, Most Frequently Between 1500 And 1700 RPM, No Diagnostic Trouble Codes \( DTC \) Generated \- All Common Rail Fuel System Chassis \- US17\+OBD16 And Newer Emissions, Commonly Model Year 2018 And Newer

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2018/MC-10142731-9999.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2018/MC-10142731-0001.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Engine, Fuel system

## Vehicles listed

- 2018 to 2019 MACK ANTHEM \(AN\)
- 2018 MACK CHU
- 2018 MACK CXU
- 2019 MACK GRANITE \(GU\)
- 2018 MACK GU
- 2018 to 2019 MACK LR
- 2018 MACK MRU
- 2019 MACK PINNACLE \(CHU\)
- 2019 MACK PINNACLE \(CXU\)

## Other bulletins for the same vehicles and component

- [M0304 EC0033 202606](/bulletins/11034136.md), 2026-06-29, Emissions: ENGINE. Mack Trucks has determined that certain vehicles equipped with a model year \(“MY”\) 2017\-2018 MP8 Turbo Compound \(TC\) engine may not meet California and Federal Regulations \(CARB\). This Recall is for updated software that will reduce the amount of time necessary for the system to operate in a cold engine warm\-up strategy and provide health monitoring of the Selective Catalyst Reduction \(SCR\).
- [M0039 032026](/bulletins/11030590.md), 2026-04-02, Emissions: ENGINE. Emissions \- EC0039 MST21 Failure to Detect P20EE \- AN, CHU.
- [M0302 022026](/bulletins/11029451.md), 2026-03-03, Emissions: ENGINE. Emissions \- Mack Trucks has determined that certain vehicles equipped with a model year \(“MY”\) 2017\-2018 MP7 engine may not meet California and Federal Regulations \(CARB\).
- [CBR 820\-9 202601](/bulletins/11028051.md), 2026-02-03, Service bulletin: ENGINE; VEHICLE SPEED CONTROL. CBR \- Mack Chassis \- Engine Brake Only Works With The Brake Pedal, No Function During Cruise. US07 And Newer Emissions, Model Year 2008 And Newer.
- [CBR 2107\-22 202601](/bulletins/11028032.md), 2026-02-02, Service bulletin: ENGINE. CBR \- Mack DEF Level \(UQLS\) Sensor Troubleshooting Guide \- US17\+OBD16 Emissions to US22\+OBD2023 \(DOES NOT APPLY TO AN\(4\) and PR\(4\)\).
- [CBR 199 202512](/bulletins/11027007.md), 2026-01-05, Service bulletin: ENGINE. Vehicles affected by this issue will show coolant runoff on the front rights side of the engine.
- [CBR 2171\-11 202511](/bulletins/11026025.md), 2025-12-03, Service bulletin: ENGINE; ELECTRICAL SYSTEM. CBR \- Mack Temperature Sensor Troubleshooting Guide
- [CBR 199\-6 202511](/bulletins/11026021.md), 2025-12-03, Service bulletin: ENGINE. CBR \- 13 Liter Engines ONLY \- Engine Coolant Pump Housing Leak; Coolant Found Around The Oil Cooler Duct Cover Or In Between The Coolant Pump Housing And Oil Cooler Housing.
- [CBR 2107\-21 202505](/bulletins/11018813.md), 2025-06-02, Service bulletin: FUEL/PROPULSION SYSTEM; ENGINE. Mack DEF Level \(UQLS\) Sensor Troubleshooting Guide \- US17\+OBD16 Emissions and Newer
- [CBR 445\- 11 202505](/bulletins/11018806.md), 2025-06-02, Service bulletin: FUEL/PROPULSION SYSTEM. Vehicles Equipped With a Common Rail Fuel System \- Aftermarket Secondary Fuel Filters, Important Information On Approved Filters \- US17\+OBD16 toUS21\+OBD23

JSON: [/v1/bulletins/10142731](/v1/bulletins/10142731)

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