Sorry, I posted by mistake only the biggining..
So.. I have the same problem again on my car.. the banging from under the car never never disapeared even when lower arms and rear stabilizer links replaced by dealer in the shop.. Now they say it is GEAR BOX problem (over the phone I could Just understand "rear clutches" and have no idea what that is).
Please share experiance before I go tommorow to dealer. I have to say that I have no trust in service guys but despite that never stopped enjoying the STR.

Thanks in advance for any help

 

here is a tsb i dont know if this is your problem is but something to check out.

S204-11v2
TECHNICAL BULLETIN
07/2004
Subject
Thump from Rear of Vehicle
Model: S-TYPE
Year: 2002.5 to 2004 VIN M45255 to N30694
Section: 204-00 Suspension System
Summary
This Technical Bulletin has been issued to address customer concerns of:
· On manual vehicles, a thump from the rear of the vehicle when changing gear.
· On automatic vehicles, thump from the rear when accelerating after a period of deceleration.
JSB-07/04-S204-11v2-EN Page 1 of 3
This version 2 has been issued for the addition of a final VIN and is a replacement for
Technical Bulletin S204-11. Please destroy all copies of S204-11 and replace it with this
Technical Bulletin S204-v2.
Action
Should a customer express concern of the issues described in the summary, two inserts are to be
installed into each bushing, in the rear drive axle/differential unit to subframe mounting bushing voids,
to restrict bush movement. Follow the workshop procedure outlined below.
Workshop Procedure
1 Raise vehicle on 'four-post' ramp.
Working on the left-side rear drive axle/differential mounting bushing:
2 Place a suitable protective material to the front face of the spare wheel well behind the left-side
bushing, to prevent damage to the spare wheel well whilst it is being levered against.
3 Using a suitable adhesive tape, secure the
protective material into position (see Fig. 1).
Fig. 1
CAUTION: DO NOT USE ANY OTHER LUBRICANT AS THIS CAN CAUSE DAMAGE TO THE
RUBBER BUSHING MATERIAL.
4 Lubricate left bushing upper void with suitable tire lubricant. If this is not available, water can be
used.
S204-11v2
JSB-07/04-S204-11v2-EN Page 2 of 3
5 Position insert to left bushing upper void (see
Fig. 2).
Fig. 2
6 Using a suitable tool, force insert part way
into left-side bushing upper void (see Fig. 3).
Fig. 3
7 Using a suitable lever positioned against the
front face of the spare wheel well protection,
lever insert fully into position (see Fig. 4).
Fig. 4
8 Place a suitable jacking device under the rear drive axle/differential.
9 Place a suitable block of wood on the jack.
10 Operate the jack to raise the rear drive
axle/differential and open up the bushing
lower void.
Note: Jack under the center of the rear
drive axle/differential to install the
left-side rear bushing lower void
insert. Jack under the right-hand
side lug to install the right-side rear
bushing lower void insert (see Fig.
5).
Fig. 5
S204-11v2
JSB-07/04-S204-11v2-EN Page 3 of 3
CAUTION: DO NOT USE ANY OTHER LUBRICANT AS THIS CAN CAUSE DAMAGE TO THE
RUBBER BUSHING MATERIAL.
11 Lubricate left bushing lower void with suitable tire lubricant. If this is not available, water can be
used.
12 Position insert to left-side bushing lower void.
13 Using a suitable tool, force insert part way into left-side bushing lower void.
14 Using a suitable lever positioned against the front face of the spare wheel well protection, lever
insert fully into position.
15 Lower jack.
16 Remove protective material, and transfer to the front face of the spare wheel well behind the rightside
bushing.
17 Carry out steps 3 to 15 to install inserts into the rear drive axle right-side bushing voids.
18 Remove block of wood from jack and place aside.
19 Remove jacking device.
20 Remove adhesive tape and protective material.
21 Lower vehicle on ramp.
Parts Information
The following parts must be ordered via Jaguar Cars Parts Operations (or through NSC/Importer).
Description Part Number Quantity
Rear drive axle/differential rear mounting bushing void inserts XR8 51446 4
Warranty Information
Description SRO Labor Time
Allowance
Causal
Part
Rear drive axle/differential rear mounting bushing service fix 64 91 15 0.3 Hours XR8 42787

 

Bobby thanx very much for this info, surely I will look into it and inform the service guys and see what happens. Will post here the results for sure as soon as I get more info on my car.
Thanx again everyone, this site is surely great coz of its people posting and sharing!