Technical Bulletin
Bulletin No: TCH-023-004
Subject:

Effective Date: 5/17/2019

Cancels: N/A

Page: 1 of 6

Disc Brakes Exhibiting Noisy Operation and / or Abnormal Pad Wear

General
Bendix Spicer Foundation Brake LLC has discovered that some 22.5” Knorr-Bremse SB-7™ or SN-7™ brake
assemblies may exhibit noisy operation and/or abnormal pad wear. The brake assembly models that exhibit
these conditions and fall within specific dates of manufacture may be covered under an extended warranty.
The following information will aid in determining if an air disc brake assembly falls within these guidelines.
Identifying Excessive Brake Noise
All disc brakes will make some noise during operation. Normal noises created by the brake are typically
relatively quiet when compared to the ambient noise of the vehicle. One of the characteristics shown by parts
impacted by this issue is a clunking or creaking noise coming from the caliper during brake applications. To
test for this condition, make a gentle service brake application – with the vehicle stationary and the wheels
chocked – and gradually increase the pressure until coming to a full pedal application. Be sure to apply at least
75 psi of application pressure. Listen for a creaking, groaning, or clunking noise coming from the suspect brake
caliper. If this noise is detected, check the identification tag to identify if the brake assembly is the appropriate
model and was manufactured during the suspect time period. Typically the noise can be heard from the driver’s
seat if it occurs on a steer axle brake. If observed directly at the wheel ends, the noise will be noticeably louder.
Identifying Abnormal Pad Wear
Another characteristic shown by parts impacted by this issue is abnormal brake wear. During a normal
maintenance inspection, look for the following conditions:
1.

The difference in pad thickness between inboard and outboard pads is greater than 3 mm; or

2.

The difference in thickness on both ends (left to right) of the same brake pad is greater than 2 mm.

For the proper procedure to measure pad thickness, refer to Knorr-Bremse service document Y006471 (SN-7)
or C16352 (SB-7) available on knorr-bremsecvs.com. If either of these conditions exist, check the identification
tag to identify if the brake assembly is the appropriate model and was manufactured during the suspect time
period.
Identifying the Manufacturing Date of the Brake Assembly
The air disc brake assemblies that qualify for the extended warranty were manufactured between January 1,
2015 & January 16, 2017. To identify the date of manufacture, first locate the identification tag on the brake
caliper as shown below. This information is presented differently between brake assemblies manufactured by
Knorr-Bremse and those manufactured by Bendix.

Identification Tag Location

Figure 1 – Brake Assembly Identification Tag Location

Bulletin No: TCH-023-004

Effective Date: 5/17/2019

Cancels: N/A

Page: 2 of 6

Knorr-Bremse Air Disc Brake Identification Tag:
Verify the brake type. This is found in the third row of numbers on the tag. The brake type must be a KnorrBremse SB-7™ or SN-7™ brake to be covered by this bulletin. (Refer to Figure 2.)
Next, look for the first six (6) digits of the date code located on the bottom line of the identification tag. These
six (6) digits of the date code can be interpreted as follows:
Digit

Description - (First six (6) Digits of the Date Code)

1

A, L, or C for the manufacturing location. (Assemblies with a letter C are not considered for the
extended warranty).

2&3

Year of manufacture. E.g., 15 = 2015 (Assemblies with 15, 16, or 17 are considered for the
extended warranty).

4&5

Production week. E.g., 36 = 36th week in the year of manufacture. (01 through 52).

6

Day in the production week. E.g., 1 = Monday, 2 = Tuesday, etc. (1 through 7).

The range of date code values pertaining to this bulletin is A or L followed by 15014 through 17031, which
represents the entire period between January 1, 2015 and January 16, 2017. An example of the KnorrBremse identification tag is shown in Figure 2.

Knorr-Bremse Identification Tag

Vehicle Manufacturer

XXXXXXXXXXXXX
XXXXXXXXXXXXXX
XXXXXX XXXXXXX

Brake Type
(Bendix® SB-7™ or SN-7™)
Date of Code

X XXXXX XXXXX

Knorr-Bremse Date Code
(X 1 5 0 1 4 x x x x x through
X 1 7 0 3 1 x x x x x with the first
digit being A or L)
Note that only the first six digits
are needed to determine if the
brake assembly is covered by
the extended warranty.

Vehicle Manufacturer's
Part No.
Knorr-Bremse
Part No.

Knorr-Bremse Date Code Interpretation
Year
(15, 16, or 17 only)

Production Week
(01 through 52)

x 15014 xxxxx
Manufacturing
Location
(A or L only)

Day of the Week
(1 through 7)

Note: X represents a placeholder for alpha and numeric characters.
Figure 2 – Knorr-Bremse Identification Tag

5 Digits (Not needed to determine
if the extended
warranty applies)

Bulletin No: TCH-023-004

Effective Date: 5/17/2019

Cancels: N/A

Page: 3 of 6

Identifying Guide Pins Manufactured During the Suspect Time Period
It is possible that a brake assembly manufactured outside the suspect date range may have been serviced with
guide pins manufactured within the suspect date range. If your brake assembly exhibits the same conditions
identified on page 1 – such as noisy operation and/or abnormal pad wear – and if it was serviced with a guide
pin kit purchased from Bendix Spicer Foundation Brake LLC or a Bendix supplier, the kit may be covered under
the extended warranty.
To determine if the guide pin kit is covered by the extended warranty it is necessary to disassemble the caliper
carrier assembly and visually inspect the guide pins. Be sure to have the appropriate replacement service
kit on-hand before beginning disassembly, as it is not possible to re-use the old parts once they have been
removed.
Once the caliper has been removed from the carrier, remove and inspect the fixed pin from the caliper assembly.
The guide pin is accessible once the retaining bolt holding the caliper to the carrier has been removed.
Inspect the end of the guide pin. If there is a groove cut in the face of the pin it is covered by the extended
warranty. If the pin does not contain a groove it does not fall within the range of suspected parts and is not
eligible for the extended warranty coverage. (Refer to Figure 3.)

Caliper Bolt
Groove
Located in
Pin Face

Guide Pin Covered Under the
Extended Warranty
Figure 3 – Guide Pin Identification

Guide Pin
No Groove
Located in
Pin Face

Guide Pin Not Covered Under
the Extended Warranty

Bulletin No: TCH-023-004

Effective Date: 5/17/2019

Cancels: N/A

Page: 4 of 6

Extended Warranty Coverage Details
Bendix Spicer Foundation Brake LLC (“Company”) extends its warranty to the original retail purchaser of
Bendix® SB-7™ and SN-7™ air disc brake products sold by the Company from two (2) years / unlimited mileage to
three (3) years / unlimited mileage if the following conditions are met:
1. The brake must exhibit excessive noise or abnormal pad wear as defined in this document.
2. The brake was manufactured between January 1, 2015 and January 16, 2017 or the guide pin was
replaced within the past 3 years.
3. Claim must be filed in the online webshop at bendix.biz.
4. Brake pads, guide pins, and bushings must be shipped to the Bendix Warranty Lab for inspection.
5. Inspection shows the guide pin is covered by the extended warranty and has led to the abnormal pad
wear as defined in this document.
This limited warranty does not cover defects or damage caused by abuse, misuse, road debris, accidents
or improper installation, maintenance or service, or use in non-standard vehicle applications that have
not been approved by the Company or which do not meet Company specifications and guidelines
(i.e. Bendix warranty coverage requires that the use or application of the products must be approved
pursuant to standard OEM and Company engineering approvals). Normal wear and tear of brake pads
or rotors (including the cast tone ring) is not covered under this limited warranty. Boot damage resulting
from road hazards or use of improper replacement tools is not covered under this limited warranty. Any
damages resulting from the use of non-OE approved replacement components, including brake pads,
rotors, or brake chambers are not covered under this limited warranty.
Product:
Product claimed to be defective must be returned – freight prepaid – via the Original Equipment (OE) dealership
or authorized company distributor within thirty (30) days after the date any defect is first discovered. Unauthorized
repairs will void this limited warranty.
The Company will inspect the product and make the final determination as to whether the product is covered
under the terms of this limited warranty. When a warranty claim is allowed, the Company’s responsibility
is limited – at the Company’s sole option – to repair or replace the defective product with a remanufactured
exchange unit. The replacement unit will be warranted for the remaining time period, mileage, or hours of the
original warranty.
Labor:
For thirty-six (36) months, unlimited miles, the Company will reimburse (at its current labor rate) applied to the
standard hours allowed in Removal and Replacement Schedule (BW1322) when the Company determines that
a defective product was installed. Labor coverage is included only when Bendix brand brake pads, rotors, and
brake chambers are used.

Refer to Figure 4 for a diagnostic flow chart that will aid in the
proper identification and diagnosis of a suspected caliper.

Bulletin No: TCH-023-004

Effective Date: 5/17/2019

Cancels: N/A

Page: 5 of 6

Loud noises from wheel-end reported.
Is the
brake assembly
a 22.5" Bendix®
SB-7™ or
SN-7™ ?

Follow the inspection process to
determine if the brake assembly is in
need of servicing and if it falls within the
3-year extended warranty guidelines.

Yes
With the wheels chocked and the vehicle
in a stationary position, make a gentle
service brake application. Gradually
increase until a full brake application of at
least 75 psi is reached. Listen for
creaking, groaning, or clunking noises
coming from the suspect caliper.

Is the
brake assembly
date of manufacture
between 1/1/2015 &
1/16/2017?

Yes

No

Continues on the
following page.

No

Yes
Are noises
present?

Covered by the 3-year
extended warranty.

No

Measure Brake Pads

Replace the brake pads &
service with a Genuine
Bendix® guide pin kit.

Yes
Is the
difference
in pad thickness
between inboard & outboard
pads greater than
3 mm?

Is the brake
assembly within the
3-year warranty
period?

No
Yes
Is the
difference in
pad thickness on both
ends of the same pad
greater
than 2 mm?

No

Yes

Process an online
warranty claim.
Return the brake pads, guide
pins, and bushings to Bendix for
warranty evaluation.

Check running clearance according
to the Service Data sheet.

Is the running
clearance within
the specification?

Yes

Inspect the brake pads
for play between the
carrier horns.

No
Is there
play between
the horns?

Check the adjuster according
to the Service Data sheet.

No

Remove dirt and
corrosion. Repair carrier
deformation if applicable.

Yes
Check the caliper guide
system according to the
Service Data sheet.

Is the
adjuster working
appropriately?

No

Replace the caliper.

Caliper guide
system OK?

Yes
Yes

Figure 4 – Diagnostic Flowchart

Not covered by this bulletin.

No

Repair the caliper guide
system according to the
Service Data sheet.

From the
following page.
Yes

Bulletin No: TCH-023-004

No

Effective Date: 5/17/2019

Cancels: N/A

Page: 6 of 6

Brake assembly not covered by
the 3-year extended warranty

From the
previous page.
No

Were the
guide pins replaced
after 1/1/2015?

Covered by the standard
2-year warranty.

No

Is the
brake assembly
within the 2-year
warranty period?

Yes

Warranty does not apply.
No

Replace the brake pads & service with
a Genuine Bendix guide pin kit.

Replace the brake pads &
service with a Genuine
Bendix® guide pin kit.
Yes
Process an online warranty claim.
Inspect the removed
guide pins.

Return the brake pads, guide pins, and
bushings to Bendix for warranty evaluation.

Do the
guide pins have a
groove in the
pin face?

No

Not covered by the
3-year extended warranty.

Yes

Continues on the
previous page.
Yes

Parts have 3-year
extended warranty.

Are the
guide pins within the
3-year extended
warranty
period?

No

The warranty has expired.

Log-on and Learn from the Best
On-line training that's available when you are
Visit brake-school.com.

24/7/365.

Figure 4 – Diagnostic Flowchart - (Continued)
Rev. 000 © 2019 Bendix Spicer Foundation Brake LLC • All Rights Reserved

Bulletin technique
No de bulletin : TCH-023-004F

Date en vigueur : 5/17/2019

Annulations : S.O.

Page : 1 sur 6

Freins à disque présentant un fonctionnement bruyant et/ou une usure anormale des
plaquettes
Objet :

Généralités
Bendix Spicer Foundation Brake LLC a découvert que certains ensembles de frein Knorr-Bremse SB-7™ ou SN-7™
de 22,5 po peuvent présenter un fonctionnement bruyant et/ou une usure anormale des plaquettes. Les modèles
d’ensembles de frein qui présentent ces conditions et qui tombent dans des dates de fabrication spécifiques peuvent
être couverts par une garantie prolongée. Les informations suivantes aideront à déterminer si un ensemble de freins
à disque pneumatique est conforme à ces directives.
Identification du bruit de frein excessif
Tous les freins à disque font du bruit pendant le fonctionnement. Les bruits normaux créés par le frein sont, en
général, relativement silencieux par rapport au bruit ambiant du véhicule. En ce qui concerne les pièces touchées
par ce problème, l’une des caractéristiques qui ressort est un bruit de cliquetis ou de grincement provenant de
l’étrier pendant l’application du frein. Pour tester cette condition, appliquez doucement le frein de service – lorsque le
véhicule à l’arrêt et que les roues sont calées – et augmentez progressivement la pression jusqu’à ce que vous arriviez
à enfoncer complètement la pédale de frein. Assurez-vous d’appliquer au moins 75 psi de pression d’application.
Écoutez les grincements, les gémissements ou les claquements provenant de l’étrier de frein suspect. Si ce bruit
est détecté, vérifiez la plaque d’identification pour déterminer si l’ensemble de frein est le modèle approprié et s’il a
été fabriqué pendant la période suspecte. En règle générale, si le bruit se produit sur un frein d’essieu directeur, il
peut être entendu depuis le siège du conducteur. S’il est entendu directement aux extrémités des roues, le bruit sera
sensiblement plus fort.
Identification de l’usure anormale des plaquettes
En ce qui concerne les pièces touchées par ce problème, une autre caractéristique est l’usure anormale des freins.
Lors d’une inspection d’entretien normal, recherchez les conditions suivantes :
1. La différence d’épaisseur des plaquettes entre les plaquettes intérieures et extérieures est supérieure à
3 mm; ou
2. La différence d’épaisseur aux deux extrémités (de gauche à droite) d’une même plaquette de frein est
supérieure à 2 mm.
Pour la procédure appropriée visant à mesurer l’épaisseur des plaquettes, consultez le document de service KnorrBremse Y006471 (SN-7) ou C16352 (SB-7) en ligne sur knorr-bremsecvs.com. Si l’une ou l’autre de ces conditions
existe, vérifiez la plaque d’identification pour déterminer si l’ensemble de frein est le modèle approprié et s’il a été
fabriqué pendant la période suspecte.
Identification de la date de fabrication de l’ensemble de frein
Les ensembles de freins à disque pneumatique qui s’appliquent à l’extension de garantie ont été fabriqués entre le
1er janvier 2015 et le 16 janvier 2017. Pour identifier la date de fabrication, repérez d’abord la plaque d’identification
située sur l’étrier de frein, comme il est illustré ci-dessous. Ces informations sont présentées de manière différente
entre les ensembles de frein fabriqués par Knorr-Bremse et ceux fabriqués par Bendix.

Emplacement de la plaque d’identification

Figure 1 – Emplacement de la plaque d’identification de l’ensemble de frein

No de bulletin : TCH-023-004F

Date en vigueur : 17/05/2019

Annulations : S.O.

Page : 2 sur 6

Plaque d’identification de frein à disque pneumatique Knorr-Bremse :
Vérifiez le type de frein. Le type est indiqué sur la plaque à la troisième ligne de chiffres. Pour être couvert par le
présent bulletin, le type de frein doit être un frein Knorr-Bremse SB-7™ ou SN-7™. (Voir figure 2.)
Ensuite, recherchez les six (6) premiers chiffres du code de date qui est situé sur la dernière ligne de la plaque
d’identification. Ces six (6) chiffres du code de date peuvent être interprétés comme suit :
Chiffre

Description – Six (6) premiers chiffres du code de date

1