# Service bulletin 26\-032

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: 10168701
- Published by NHTSA: 2019\-12\-04
- Manufacturer's number: 26\-032
- Manufacturer's date: 2019\-11\-07
- NHTSA component: ENGINE AND ENGINE COOLING; POWER TRAIN

## NHTSA's summary

Non\-Safety Campaign: Certain chassis built between March 01, 2017 and August 26, 2019 that are equipped with MX\-11/MX\-13 EPA2017 engines, and with Eaton UltraShift or Fuller transmissions may experience an engine overspeed error when going downhill. New shift calibrations have improved protective upshift logic to allow upshift sooner when approaching overspeed conditions. Resolution is to update the transmission software and shift calibration software.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2019/MC-10168701-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2019/MC-10168701-9999.pdf)

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

## Components

Engine, Transmission and driveline

## Vehicles listed

- PETERBILT PETERBILT

JSON: [/v1/bulletins/10168701](/v1/bulletins/10168701)

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