18 12 031 Replacing left or right rear silencer (N63)

WARNING: This page is about a different car, the 2013 BMW 550i GT, 2012 BMW 550i GT, 2011 BMW 550i GT, and 2010 BMW 550i GT. However, it is still accessible from the selected car via links, so may be relevant.

Special tools required:

31 2 220

WARNING: Risk of burning!
This repair work may only be carried out on an exhaust system which has cooled down.

Support rear silencer with special tool 31 2 220 and a suitable universal lifter.

Fig 1: Supporting Silencer Using Special Tool (31 2 220)

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NOTE: If the separation point line is not marked by a punch mark in the pipe, determine the separation point by means of the pipe length on the new rear silencer.
Carry over separation point to faulty rear silencer and mark.
Secure rear silencer against falling off.
Cut through exhaust pipes at marked point with a suitable tool.

Fig 2: Identifying Cutting Marks On Exhaust Pipes

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Picture shows the left side, the procedure for the right side is identical.

Slacken nut (1).

Tightening torque 18 20 5AZ.

Fig 3: Identifying Silencer Nut

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Picture shows the left side, the procedure for the right side is identical.

Slacken nut (1).

Tightening torque 18 20 5AZ.

Detach hose (2) on vacuum unit.

Installation note:

Check vacuum hose (2) for damages. Replace damaged section of vacuum line and protect it with a woven protective hose.

Fig 4: Identifying Vacuum Unit Hose And Nut

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Lower and remove rear silencer with assistance of a second person.

Installation note:

Install, adjust new rear silencer and connect with hose clamp.

Turn clamps with the screw connection inward. Clamps must have a distance of 22 mm to bordering components and have reinforcing struts!

Centre clamp and tighten down.

Tightening torque 18 31 4AZ.

Fig 5: Identifying Centre Muffler Clamps

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The procedure is identical on both sides.

NOTE: Check rubber mount for damage.
Replace damaged rubber mount.
Check exhaust system for leaks.