18 12 050 Replacing centre muffler (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: Scalding hazard!
Only perform these tasks after exhaust system has cooled down.

Support centre 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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Release screws (1).

Remove heat shield (2).

Fig 2: Identifying Heat Shield And Screws

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Release screws (1).

Tightening torque 18 20 6AZ.

Only when independent heating is fitted: release screw (2) on metering pump.

Tightening torque 18 20 7AZ.

Release screws (3) on underbody panels.

Remove reinforcement plate (4).

Fig 3: Identifying Reinforcement Plate, Metering Pump And Underbody Panel Screws

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

Fig 4: 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 4AZ.

Fig 5: Identifying Exhaust System Nut

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Installation:

Adjust centre muffler to fit and connect with clamps.

Centre clamp and tighten down.

Tightening torque 18 31 4AZ.

The procedure is identical on both sides.

Fig 6: Identifying Centre Muffler Clamps

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NOTE: Check exhaust system for leaks.