2000 BMW 328i (E46) Technical Service Bulletin # 410408 Date: 091001
Body/Drivetrain - Rear Axle Support Repair Procedures
SI B41 04 08
Body
October 2009
Technical Service
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This Service Information bulletin supersedes SI B41 04 08 dated August 2009.
[NEW]designates changes to this revision
SUBJECT
Rear Axle Support Repair Procedure
MODEL
E46 (3 Series)
SITUATION
Under certain circumstances, a fracture in the steel body structure could form in the area around one of the rear axle carrier mounting points. As a
result, a distinct clicking noise can be heard from the area of the rear axle carrier during certain driving conditions. Specifically, the noise may be
heard during load reversals on the rear axle, such as when starting from a stop, engaging forward or reverse gears, or when rapidly changing gears.
A repair procedure has been developed to repair damage to the rear axle support where the rear axle carrier is secured to it. This repair procedure is
not included in the repair manual in the Technical Information System (TIS).
If damage is found in the area of the left rear of the rear axle support, the procedure shown in this bulletin should be used to determine the
appropriate repair procedure.
CAUSE
Details surrounding these repair procedures are not included in TIS.
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PARTS INFORMATION
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WARRANTY INFORMATION
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Attachment - B410408A Applicator Order Form
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Attachment - B410408RA4111400_05-09
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Attachment - B410408FR Description
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Attachment - B410408 Labor Operations
Information
The following procedures apply only to cracks found at or around the left rear mounting point for the rear axle carrier.
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Visually inspect the left rear mounting point for the rear axle carrier (left leader for #1 illustrated). If a fracture in the sheet metal is present, the
length of the crack must be measured. If multiple cracks are present, measure the longest one.
The damage identified must be documented with a clear digital photo, printed out, and included in the vehicle's file.
^ If the length is 20mm or less and the vehicle was produced prior to 10/2004, proceed to Procedure A.
^ If the length is 20mm or less and the vehicle was produced from 10/2004, proceed to Procedure B.
^ If the length is greater than 20mm, proceed to Procedure B. For technical assistance with either of the following repairs, please contact your
Regional Technical Engineer.
A. Crack 20mm or Less In Length (Structural Epoxy)
A. Crack 20mm or less in length (structural epoxy):
The following procedure is to be followed to fill the cavity above the left rear mounting point for the rear axle carrier with structural epoxy. This
structural epoxy will both reinforce the affected area, as well as help prevent future damage to it.
NOTE:
The following procedure is for an E46 coupe, but can be used on all variants knowing that there may be some minor deviations. In addition, the
following procedure should be performed with the vehicle in a location where it can stay for 24 hours following the repair, to allow the epoxy to
cure.
1. Remove the floor trim from the luggage compartment
2. Perform all applicable safety precautions when working with seam sealer and structural epoxy.
3. This illustration identifies the area inside the trunk where the following procedure will take place.
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4. Identify the following 3 points which will be used in this repair. This area is located above the left rear mounting point for the rear axle carrier.
Holes (2) and (3) will be filled with urethane seam sealer to create a barrier and thus a sealed cavity. Hole (1) will be filled with 2 complete
cartridges of structural epoxy. These 3 holes will be referenced by number throughout this procedure.
5. Hole (1) is present and is sealed with a body plug.
Hole (2) is not present and must be drilled. It should be drilled halfway between Hole (1) and the similar hole on the right side of the luggage
compartment. A 10mm stepped drill bit should be used.
Hole (3) is present but is covered by the anti-vibration liner. Locate the hole using the dimensions provided and expose the hole using suitable tools.
6. Use a length of tape or a body plug to seal the hole (1) from the underside of the vehicle if it is present on the vehicle.
This hole is located immediately to the right side of the left rear mount for the rear axle support (2).
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7. Prepare to install the seam sealer into Holes 2 and 3 from Step 4 by placing a 250mm (10") length of 3/8" clear flexible tubing (locally sourced)
onto the nozzle of an open cartridge.
8. Looking at the bottom of the seam sealer cartridge, measure and record the distance to the plunger (A). This is necessary to ensure the correct
amount of seam sealer has been injected since it's a blind operation.
9. Place a tape line on the tube 120mm (4-3/4") from the open end. Insert the tube (1) into Hole 2 up to the tape line. Directly below Hole 2 is an
existing hole (2) of similar diameter. The plastic tube must go through this hole and reach the bottom of the cavity. This illustration shows a cutaway
view to illustrate the triangular shape (3) of the cavity which is to be filled.
10. Inject the seam sealer while slowly pulling back on the plastic tube to create a vertical barrier in the cavity. The amount of material that must be
injected is the equivalent of 12mm of travel of the cartridge plunger.
11. Once the seam sealer has been installed, measure the position of the plunger again to ensure that it has traveled 12mm from the position
previously recorded in Step 8.
12. Measure and record the position of the plunger similar to Step 8. The area under Hole 3 will be filled next and is much smaller than Hole 2.
Therefore the plunger in the seam sealer cartridge only needs to be depressed by 2mm.
13. Insert the plastic tube into Hole 3 (identified in Step 4) and fill the cavity with seam sealer.
14. Once the seam sealer has been installed, measure the position of the plunger again to ensure that it has traveled 2mm.
15. Wait at least 10 minutes for the seam sealer to set before continuing with the next step, structural epoxy installation.
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16. Remove the fastening nut and sealing plug from the structural epoxy cartridge. Next, install the mixing nozzle (1) onto the cartridge pack and
secure it with the fastening nut (2), both of which are supplied with the cartridge pack.
17. Install the included extension tube (1) over the end of the mixing tube (2).
18. Due to the high viscosity of the two part structural epoxy, it must be warmed in order to flow out of the cartridge pack properly, and into the void
it is intended to fill. Two cartridge packs are required for this repair. Place both cartridges packs under hot running water or in a large pail of hot
water for 15-20 minutes to heat the contents thoroughly.
19. ct the recommended pneumatic applicator to a shop air supply. A pneumatic applicator is recommended as a manual applicator can make it
difficult to fully fill the necessary cavity. The recommended applicator is the same one previously recommended for use in SI B54 04 08.
20. Feed the flexible extension tube into Hole (1). About 10mm below
this hole is another hole which this tube must be fed through.
21. Inject the entire contents into the cavity. The red line on the side of the applicator will display how much has been injected. If the material begins
to flow too slowly, warm the cartridge pack with an electric heat gun (set to low heat) to improve the flow.
NOTE:
Take appropriate safety precautions when using a heat gun, and be sure not to heat the cartridge too aggressively as the plastic cartridge container
could melt.
22. Remove the flexible tube and repeat steps 19 20 with a second, already warmed cartridge pack.
23. Remove any protruding structural epoxy while it's still flexible and seal the holes with body plugs.
24. Reassemble the vehicle and allow the epoxy to cure for a minimum of 24 hours.
NOTE:
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The vehicle must not be moved until the structural epoxy is fully cured.
B. Crack Greater Than 20mm In Length
B. Crack greater than 20mm in length (replace rear axle carrier support):
1. Replace the replacement rear axle support per the copy shown in this bulletin of repair instruction RA41 11 400.
NOTE:
No modifications to the repair part are required or recommended.
^ [NEW]For a list of jobs/labor operations needed for this repair, as stated in KSD, please refer to the document, FR Description 0054198. This
document is an example for a specific E46 variant; therefore, some variation may exist based on the variant in question.
^ [NEW]For a list of jobs/labor operations needed for this repair, as well as labor allowances that may be claimed via sublet, refer to the document
B410408 Sublet Labor Operations.pdf. In addition, this document separates Labor types (Body vs. Mechanical).
2. Depending on which straightening bench is used, some additional procedures in addition to those listed in RA4111400 may need to be performed
in order to properly mount the vehicle on the straightening bench.
NOTE:
This repair should be performed by a BMW operated or BMW recommended body shop.
3. On cars produced prior to 3/99, the two studs located above the fuel tank which retain the brake and fuel lines, are in a different location to that of
the replacement rear axle support. If the car was produced up to 3/99:
a. Cut off the two studs on the replacement part.
b. After installing the replacement rear axle support, position the brake and fuel lines to the floor pan, using the same clip previously removed.
Clean the surface and mark the center hole in the clip that holds them in place.
c. Weld on two new studs (locally sourced) at this marked location.
d. Prime and undercoat the cleaned area around the studs.
4. When performing this repair on an M3 or any Convertible model, the forward mounting brackets (located under the rocker panels), which the
v-support secures to, must not be removed. It is not necessary to remove them for this repair, and replacement brackets are not available as a spare
part.
5. Replace fasteners and small items as necessary.
6. It is necessary to perform a four wheel alignment following this repair. If the alignment cannot be brought into specification due to damaged or
worn suspension components, the customer can opt to have these replaced at their cost.
