SAE J2786-2017 PDF

Full title and description

SAE J2786-2017 — Automotive Brake Noise and Vibration Standard Nomenclature. This SAE recommended practice provides standardized terminology and definitions for noises and vibrations attributed to foundation brake components (disc and drum brakes) on passenger cars and light trucks, covering tactile sensations through audible frequencies up to about 17 kHz.

Abstract

Defines nomenclature for brake-related noise and vibration (NVH) phenomena to enable consistent classification, reporting and communication across engineering, testing and supplier organizations. The document clarifies terms used to describe causes, manifestations and perceptual characteristics of brake noise and vibration events originating in foundation brake systems.

General information

• Status: Stabilized / Active (revised and stabilized in December 2017).
• Publication date: December 20, 2017 (J2786_201712; revision of the original J2786 issued 2009).
• Publisher: SAE International (Society of Automotive Engineers).
• ICS / categories: Road vehicle engineering — Braking systems (ICS 43.040.40 and related road-vehicle categories).
• Edition / version: J2786_201712 (stabilized edition, revision of J2786-2009).
• Number of pages: 4–5 pages (SAE Mobilus lists 5 pages for the 2017 stabilized document).

Scope

Applies to terminology and definitions for noises and vibrations arising from foundation brake components on passenger cars and light trucks. The scope covers both disc and drum brakes and spans phenomena from near-zero Hz tactile sensations to the upper limit of normal hearing (~17 kHz). The intent is to establish common language for NVH characterization, root-cause communication and documentation among OEMs, suppliers and testing organizations.

Key topics and requirements

• Standardized definitions for brake-related noise and vibration events (squeal, judder, groan, rattle, tactile sensations, etc.).
• Frequency range guidance — from near 0 Hz tactile response to about 17 kHz (audible limit).
• Coverage of foundation brake system sources (pads, rotors/drums, calipers, hardware) and how those sources couple into vehicle structure and acoustic radiation.
• Terminology intended to support NVH testing, reporting and cross-organizational problem solving (consistent labels for phenomena and measurement descriptors).

Typical use and users

Used by brake NVH engineers, test-lab personnel, component and friction-material suppliers, vehicle system integration teams and technical authors preparing test reports or warranty analyses. Organizations reference J2786 when classifying noise complaints, preparing NVH test plans, or documenting root-cause findings to ensure consistent communication.

Related standards

Relevant documents include the earlier SAE J2786-2009 (the prior edition), SAE recommended practices and test procedures for brake components such as SAE J2686 (Brake Drum Qualification Recommended Practice) and other SAE/ISO brake NVH or friction-material test standards. International ISO standards on brake lining and friction behaviour (for example ISO 26865 and ISO 26867) are also commonly used alongside J2786 for testing and performance context.

Keywords

brake noise, brake vibration, NVH, nomenclature, terminology, disc brake, drum brake, brake squeal, brake judder, tactile sensation, brake diagnostics, foundation brake components.

FAQ

Q: What is this standard?

A: SAE J2786-2017 is an SAE recommended practice that defines standardized terminology and definitions for noises and vibrations produced by vehicle foundation brake systems, intended to harmonize how those phenomena are described and reported.

Q: What does it cover?

A: It covers nomenclature for brake-originated noise and vibration events (disc and drum brakes), including descriptive terms, perceptual categories and the frequency range of interest (near 0 Hz to ~17 kHz), so that engineers and technicians use consistent language in testing, reporting and root-cause analysis.

Q: Who typically uses it?

A: Brake NVH engineers, test laboratories, friction-material and hardware suppliers, vehicle integration teams, and warranty/diagnostics groups use J2786 to classify and communicate brake noise and vibration issues.

Q: Is it current or superseded?

A: The 2017 edition (J2786_201712) is the stabilized revision of the original 2009 document; it is the current SAE stabilized recommended practice as of the December 2017 revision. Users should check SAE Mobilus or SAE International for any later revisions or amendments.

Q: Is it part of a series?

A: J2786 is part of SAE’s body of brake- and NVH-related recommended practices and test procedures; it is often referenced alongside other SAE brake standards and related ISO test/performance standards when performing brake NVH evaluations.

Q: What are the key keywords?

A: brake noise, vibration, NVH, nomenclature, terminology, disc brake, drum brake, squeal, judder, tactile sensation.