18 12 031 Replacing left or right rear silencer (N55)

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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 Exhaust System With 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 Points On Pipes

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Slacken nut (1).

Tightening torque 18 31 3AZ .

Fig 3: Identifying Nut

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Slacken nut (1).

Tightening torque 18 31 3AZ .

Fig 4: Identifying Nut

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

Spray bolt (1) and rubber mount with lubricant 5.2 .

Release screw (1).

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

Installation note:

Risk of damage to bolt (1) and retaining plate thread.

Observe screwing sequence.

Firstly apply nut to body at rear.
Then join bolt (1) exactly and secure. If necessary support rear silencer using a suitable jack.
Tightening torque 18 31 3AZ .

Fig 5: Identifying Bolt

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Installation note:

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

Center clamp and tighten down.

Tightening torque 18 31 7AZ .

The procedure is identical on both sides.

Fig 6: Identifying Clamps

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

04 1820 Exhaust system suspension

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