18 12 031 Replacing left or right rear silencer (N74)

Only perform these tasks after exhaust system has cooled down.

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

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

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Secure rear silencer against falling off.

Cut through exhaust pipes at marked point with a suitable tool.

Fig 2: Identifying Rear Silencer Components

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

Slacken nut (1).

Tightening torque: see 1AZ in 18 20 EXHAUST SYSTEM SUSPENSION

Fig 3: Identifying Left Side Nuts

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

Detach hose (1) on vacuum unit.

Slacken nut (2).

Tightening torque: see 1AZ in 18 20 EXHAUST SYSTEM SUSPENSION

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

Fig 4: Identifying Vacuum Unit Hose And Nut

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Installation note: 

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

Centre clamp and tighten down.

Tightening torque: see 2AZ in 18 31 EXHAUST SYSTEM

The procedure is identical on both sides.

Fig 5: Identifying Rear Silencer Centre Clamp

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