2046299/9

Technical product information
Topic
Market area
Brand
Transaction No.
Level
Status
Release date
Bentayga - 1.2 - 1.4KHz rear brake squeal
Bentley: worldwide (2WBE),Hongkong-Macau (5HK)
Bentley
2046299/9
EH
Approval
New customer code
Object of complaint
Complaint type
Position
running gear -> brakes, brake control -> service brake noise, vibration -> noise
New workshop code
Object of complaint
Complaint type
Position
running gear -> brake system -> brake pads (disc brake) noise, vibration -> noise rear left
running gear -> brake system -> brake pads (disc brake) noise, vibration -> noise rear right
Vehicle data
Bentayga series
Sales types
Type MY Brand Designation Engine code Gearbox code Final drive code
4V1*
4V1*
4V1*
4V1*
4V1*
2017
2018
2019
2020
2021
E
E
E
E
E
Documents
Document name
master.xml
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*
*
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Technical product information
Bentayga - 1.2 - 1.4KHz rear brake squeal
Transaction No.: 2046299/9
Customer statement / workshop findings
Squeal from the rear of the vehicle at low speed while braking.
Technical background
While braking at low speed, a vibration of 1.2 to 1.4 KHz can be produced by the friction between the rear brake pad and disc resulting in a
complaint of brake noise from the customer
Production change
-
Measure
1) Follow the ‘Brake noise identification’ TPI 2052785 - IMPORTANT: For frequency analysis the noise recording equipment Bentley Motors
recommends is the Chassis ear tool WT 10437
2) If the sound recording produces a frequency of 1.2-1.4KHz
•
Remove the rear brake pads
•
Referring to Figure 1 - Take clear photographs of all four brake pad markings NOTE: Although Figure 1 shows two brake pads,
photographs of all four brake pads should be taken
Figure 1
•
Attach the photographs of each individual rear brake pad to a new or existing DISS query
IMPORTANT: Prior to ordering the shim set for the rear brake pads, please ensure all required information is attached to a new or
existing DISS query including photographs of each individual brake pad and supporting evidence that the rear brake noise frequency
is between 1.2 and 1.4KHz
•
Fit the shim set 36A 698 219 to the rear brake pads (the kit consists of one shim per pad)
NOTE: G052 560 A2 “Vary Bond Regular Grade Grease”(100 gram tube) is also required to be used in conjunction with the shims
VERY IMPORTANT: The application of the grease MUST be exactly as shown/detailed, Ensuring the exact amount of grease is
applied to the locations shown
NOTE: Warranty payments for repeat repairs will not be considered if the grease is deemed to have not been applied
correctly
3) Remove the rear brake pads as per Repair manual Rep.Gr 46 - Rear Brake Pads - To Remove and Fit and check the actual condition of the
brake pads - If the brake pads are to be refitted it will be necessary to make note of the position of the pads for installation purposes.
CAUTION: The performance of the car will be affected if the brake pads are installed in the incorrect position
If new brake pads are required, photographic evidence of the pad thicknesses and the back plate of the pads must be supplied
through a DISS technical query.
IMPORTANT: The following instructions regarding grease application must also be followed regardless if the brake pads are to be replaced or
renewed
4) Carefully clean the back plate of the pad using a suitable brake cleaner IMPORTANT: Take care not to damage the rubber on the bonded
shim NOTE: In the event that the rubber is damaged from contact with the piston and there are loose rubber parts, it would be advised to fit new
brake pads.
5) The next step is to install one shim from the shim kit 36A 698 219 to each rear brake pad, ensuring that when fitted the new shim is seated
flat against the brake pad bonded shim
6) Referring to Figure 2 - Apply 6 dots of grease (< 1.0g in total) to the inside face of the clip on shim
Figure 2
•
Referring to Figure 3 – Using a suitable spatula spread the grease to an even layer condition
Figure 3
7) Assemble the clip-on shim onto the pad - Squeeze together firmly to remove any excess grease which comes out from between the new shim
and the brake pad bonded shim NOTE: Ensure the new shim is seated flat against the brake pad bonded shim
•
Referring to Figures 4 and 5 Clean the pad abutments & the spring clips, then apply a small dot of grease to them
Figure 4
Figure 5
8) Clean the pad abutment faces on the calliper carrier – scrape off any dirt and brake dust which has accumulated, then use a suitable brake
cleaner
9) Wipe the face of the piston to remove any brake dust or dirt.
•
Refit the rear brake pads as per Repair manual Rep.Gr 46 - Rear Brake Pads - To Remove and Fit, taking care not to dis-lodge the
grease/shims before the pads are in position.
•
Conduct a road test and carry out the brake conditioning process for Iron brake systems from operation 1 through to 7 observing all
instructions relating to speed and brake effort
•
For all vehicles with Iron brake systems the 100 km/h or 60 mph to 0 must be repeated twice
When carrying out the brake pad conditioning (bedding in) process you must adhere to all local speed limits and restrictions
Brake conditioning process ( Iron brakes)
Brake pedal
operation
Initial Speed ( km/h
– mph)
Final speed ( km/h Deceleration
– mph)
Operation 1
100 km/h or 60 mph 40 km/h or 25 mph (light braking) approximately 5% 1 km or 0.6 miles
of total braking effort
10
Operation 2
120 km/h or 70 mph 40 km/h or 25 mph Increase braking effort 10%
above operation 1
1 km or 0.6 miles
3
Operation 3
120 km/h or 70 mph 40 km/h or 25 mph Increase braking effort 10%
above operation 2
1 km or 0.6 miles
3
Cycle Distance
Number of cycles
Operation 4
120 km/h or 70 mph 40 km/h or 25 mph Increase braking effort 10%
above operation 3
Operation 5
100 km/h or 60 mph
Operation 6
120 km/h or 70 mph 40 km/h or 25 mph Braking effort to be 10% above 1 km or 0.6 miles
operation 3
Operation 7
Return to the
dealership
0
(Full braking)
40 km/h or 25 mph Normal braking
applications
1 km or 0.6 miles
Repeat
N/A
3
2
10
N/A
10) On return to the workshop, visually check for any excess grease which may have come out from between the two shims and remove with
suitable cleaner.
Warranty accounting instructions
4 Brake pads - Repaired
Warranty Type 110 or 910
Damage Service Number 46 38
Damage Code
00 20
Labour
Labour Operation Code 46 38 42 50
Time 20 Time units
4 Brake pads - Rear - Removed and Refitted
Labour
Labour Operation Code 46 38 20 50
Time
50
Time
units
2 Wheels Removed and Refitted
Labour
Labour Operation Code 44 05 20 00
Time 10 Time units
Frequency diagnosis including road test
Labour
Labour Operation Code 47 01 01 00
Time
80 Time units (includes road test 01 21 00 00 - 50 Time units)
Parts information
Part number
Description
Quantity
36A 698 219 Shim set for rear brake pads 1
G 052 560 A2 Vary Bond grease
1 = 1 x 100 gram tube
Do not order x1 tube of grease for each individual vehicle as the grease must be used on multiple vehicles ( minimum of three vehicles
per tube)
IMPORTANT: Prior to ordering the shim set for the rear brake pads, please ensure all required information is attached to a new or
existing DISS query including photographs of each individual brake pad and supporting evidence that the rear brake noise frequency
is between 1.2 and 1.4KHz