# Service bulletin SD\-26\-1852

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: 11032884
- Published by NHTSA: 2026\-05\-21
- Manufacturer's number: SD\-26\-1852
- Manufacturer's date: 2026\-05\-21
- NHTSA component: SERVICE BRAKES
- Manufacturer's system: Pneumatic System: Double\-check valve

## NHTSA's summary

Service Data The Bendix® DC\-4000™ double check valve is used in an air brake system to direct a flow of air into a common line from either of two sources, whichever is at the higher pressure. The valves may be used for directing air flow for specific functions or to select the higher pressure of either of two sources of air as a supply source. Bendix manufactures multiple types of double check valves; one type is mounted in the air line without being secured to the vehicle frame, and another type contains a mounting tab to secure it to the vehicle frame or chassis. Although the valves are somewhat different physically, the same function is performed by each type.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11032884-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11032884-9999.pdf)

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

## Components

Brakes

## Vehicles listed

- BENDIX SERVICE BRAKES AIR

JSON: [/v1/bulletins/11032884](/v1/bulletins/11032884)

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