Technical product information

Technical product information
Topic

New Continental GT steering shimmy/vibration-21 Inch wheels only

Market area

Worldwide Bentley (1WBE)

Brand

Bentley

Transaction No. 2030348/1
Level

EH

Status

Approval

Release date
New customer code
Object of complaint

Complaint type

Position

Running gear-> Wheels, tyres, tyre pressure monitoring -> visual appeal I surface -> >not
Tyres -> Tyre tread
Running gear-> Steering, power-assisted steering ->
Steer

bump

specified<

Noise, vibration -> vibrate

Running gear-> Steering system

functionality

Running gear-> Steering system

Noise, vibration

New workshop code
Object of complaint

Complaint type

Position

Running gear-> Wheels, tyres, tyre pressure

component I consumables ->

monitoring -> Tyres

unbalanced

Running gear-> Wheels, tyres, tyre pressure

component I consumables ->

front

monitoring -> Tyres

unbalanced

right

Running gear-> Wheels, tyres, tyre pressure

component I consumables ->

monitoring -> Tyres

unbalanced

Running gear -> Wheels, tyres, tyre pressure

component I consumables ->

monitoring -> Tyres

unbalanced

Running gear-> Steering system -> Steering gear

Noise, vibration -> noise

rear right

front left

rear left

Technical product information

Vehicle data
New Continental GT
Sales types
Type MY Brand Designation Engine code Gearbox code Final drive code

*

393* 2012 E

*

*

Chassis numbers
Manufacturer Filler Type Filler MY Factory
SCB

*

3W

*

c c

SCB

*

ZA

*

c c

From

To

Prod from Prod to

Documents
Document name
master.xml

II

Technical product information

Customer statement I workshop findings
This TPI is only applicable to New Continental GT fitted with 21 Inch wheels.
Should a customer complain of steering wheel shimmy/vibration constantly above 80 kph/50 mph and
the condition does not improve when driven please proceed with this TPI, should the vehicle exhibit
different symptoms than described please raise a DISS ticket.

Technical background
We are aware that under certain conditions of shipment and storage, particularly involving large
changes in ambient temperature, condition can occur where the tread surface of the tyre forming the
footprint on the road surface or container floor partly retains the relatively flat form when driven and
does not immediately restore to a constant radius. Hence the name of flat spotting which is generally
given to this condition.
It should not be confused with out of balance, out of round or radial force variation. It is very important
that the diagnosis and correction of these different conditions are not confused with each
other. Attempting to correct flat spotting by rebalancing the assembly will not correct the problem and
worse still, when the flat spots are removed the tyres will then be out of balance.
The Measure section of this TPI describes the procedure which should be followed to determine the
root cause of the steering shimmy/vibration.

Production change
Improved shipping, transportation and production procedures have been introduced.

Right Hand Drive
From VIN SCBFE63WXCC

the latest level higher friction steering rack and updated servotronic

control units were fitted

Left Hand Drive
From VIN SCBFR7ZA3CC

the latest level higher friction steering rack and updated servotronic

control units were fitted

Measure
IMPORTANT: Do Not initially balance the wheel and tyre assemblies

Technical product information

ATIENTION: During this TPI the Workshop Manual is quoted to help in carrying out various tasks, it is
recommended that the procedures referenced are checked by the operative as the process within the
Workshop manual may have changed since last viewed.
- Check all wheels and tyres for damage
- Check that Bentley 21 inch approved wheels are fitted and the tyres are to the correct specification
- Check the suspension and steering components for damage
1. With the tyres set at 'Normal pressure' please follow the points below
- Drive the car until the flat spots come out or the flat spotting condition improves, then drive for
approximately 10 minutes at the lowest speed possible to allow cooling
- Within a maximum of two minutes of returning from the road test, raise the vehicle off the ground
2. Remove all four wheel assemblies Refer to Workshop Manual Rep.Gr 44
3. Using the Hunter GSP 9712 (VAS 6230) vibration control balancer (or similar) force match and
balance all four assemblies, the assembly Radial Force Variation (RFV) should not exceed 85N. RFV
must be measured with the tyres set at 3.0 Bar. Refer to Workshop Manual Rep.Gr 44 and also
observe the following key points.
- For Hunter GSP 9712 use the White faced adaptor cone with identification code 154 F+ shown in
Figure 1.
- The cone must be fitted on the spindle as shown in Figure 2 ensuring the White face of the cone is
facing towards the end of the spindle

Figure 1

Figure 2

Technical product information

NOTE: The assembly Radial Force Variation {RFV) must not exceed 85N. RFV must be measured
with the tyres set at 3.0 Bar. Refer to Workshop Manual Rep.Gr 44 Tyres - Checking Condition and
Replacement - Radial force variation - Best fit practice
Important: When conducting the wheel and tyre force matching process or should the tyres require
replacing, a specific tyre fitting lubricant should be used. The lubricant is Rema Tip Top Anti Gliss
Lube with the Bentley Part Number of RH 14530. On drying the Anti Gliss has adhesive properties that
increases friction between the tyre and wheel rim to prevent slippage. Please Refer to Workshop
Manual Rep.Gr 44 Tyres - Checking Condition and Replacement - Radial force variation - Best fit
practice.
- The assembly high spot is identified with a brown dash (Figure 3).

Figure 3
- Rotate the assembly on the spindle until the high point is at 12 o'clock and the Brown dash turns to
Green (Figure 4).

Figure 4
- Mark the RFV high point with a paint pen or similar (Figure 5) this will be required when refitting the
wheels as detailed within the Workshop manual Rep.Gr 44 Tyres - Checking Condition and
Replacement- Radial force variation - Best fit practice

Technical product information

Figure 5
4. Have the steering rack and servotronic control unit been previously replaced using the latest
specification parts? Please look for the Blue paint completion mark as shown in Figure 6 (for
steering rack) and Figure 7 for (servotronic control unit), and also check "Repair history" (in Elsa
pro) should it be evident that the rack and servotronic control unit have not been previously
replaced please go straight to procedure 5
- If both parts have been previously replaced, refit all four road wheels Refer to Workshop
manual Rep.Gr 44 ensuring the Best fit practice is adhered to.
- Road test the vehicle and reassess, should the steering shimmy issue still be evident raise a
DISS ticket, please ensure that TSC are informed that the steering rack and servotronic control
unit have been previously fitted
5. Replace the steering rack - Refer to Workshop manual Rep.Gr 48

6. Place a small blue paint completion mark on the power steering reservoir as shown in Figure 6 to
confirm the steering rack has been replaced.

Figure 6
7. Ensure the ignition is switched off then remove the UH boot panel and locate the servotronic control
unit (Figure 7)

Technical product information

Figure 7
- Remove and discard the original control unit
- Fit the replacement servotronic control unit with part number 3WO 907 307L
- Place a Blue paint completion mark on the new servotronic control unit to confirm the unit has been
replaced (Figure 8)

Figure 8

8. Refit all four road wheels, Refer to Workshop manual Rep.Gr 44 Tyres - Checking Condition and
Replacement - Radial force variation - Best fit practice

9. Road test the vehicle and reassess

NOTE: Should the condition still be evident please raise a DISS ticket and wait for further instruction
from TSC before commencing with any other work.

Warranty accounting instructions
Please Note: Normal Warranty policies are applicable.
Time to cany out the initial flat spot recovery process and force match and balance all four assemblies
Warranty Type

910 or 110

Technical product information

Labour operation code

44 40 94 00

Damage Service Number

44 40

Damage code

00 13

Time

Shop Time

Time to replace steering rack.
Warranty Type

910 or 110

Labour operation .code

48 40 19 00

Damage Service Number

4840

Damage Code

00 13

Time

270 Time units

Time to replace servotronic control unit
Warranty Type

910 or 110

Labour operation code

48 69 19 00

Damage Service Number

48 69

Damage Code

00 13

Time

10 Time units/6 Minutes

Time to check and set the vehicle geometry without ACC
Warranty Type

910 or 110

Labour operation code

44 95 03 00

Damage Service Number

44 95

Damage Code

00 13

Time

80 Time units/48 Minutes

Time to check and set the vehicle geometry with ACC
Warranty Type

910 or 110

Labour operation code

44 95 03 10

Damage Service Number

44 95

Damage Code

00 13

Time

150 Time units/90 Minutes

Parts information

0

Technical product information

Description

Part Number

Quantity

Steering Rack (LHD)

3W1422061D

1

Steering Rack (RHD)

3W2 422 061D

1

Servotronic control unit 3WO 907 307L

1

Bolt

N10211202

2

Bolt

N10 625 601

1

N10 518 404

1

Bolt

N90 966 002

2

Lock screw

WHT 001480

2

Nut

N10 272 302

2

Nut

N90 892 302

2

Bolt

N10 491 802

2

Washer

N10 406 105

2

Steering fluid

JNV 862 564F

2 Litres

Seal washer

N0138494

2

Seal washer

N0138486

2

Anti Gliss

RH 14530

1 x 500 Gram tin can be used for multiple

Steering column bolt
'

applications

n

Technical product information

Customer information
The customer may notice an initial difference in the feel of the steering, however this is normal, the
difference is due to the fitment of the latest level higher friction steering rack.
Bentley branded Tyre Cradles are available as an approved accessory.
The tyre cradles have been designed and manufactured specifically for Bentley providing simple and
effective tyre protection.
Tyre flat spotting can be caused by medium to long term storage or from parking after a long drive,
especially where the tyre experiences large changes in temperature.
To prevent flat spotting, tyres need to be cooled in a controlled manner to enable the tyre to restore to
a constant radius.
Made from a unique polymer that moulds to the shape of the tyre the new Bentley Tyre Cradles
maintain the tyre shape whilst cooling and in storage.
The tyre cradles are easy to use, simply drive the car onto them in the desired parking area.