Exhaust System

General Information
The exhaust system consists of two front pipes which, on models 520i, 523i and 525tds, are installed upstream of the catalytic converter. The auxiliary and main mufflers are installed downstream.

Exhaust system, models 520i, 523i
1 — nut
2 — gasket
3 — front pipe with catalytic
converter
4 — clamp
5 — auxiliary muffler
6 — bolt
7 — crossmember
8 — rubber mount
9 — vibration damper
10 — main muffler

Exhaust system, model 525tds
1 — nut
2 — front pipe
3 — catalytic converter
4 — clamp
5 — bolt
6 — auxiliary muffler
7 — crossmember
8 — rubber mount

On model 528i, the exhaust system in the area of the catalytic converter and tailpipe is dual-flow. Oxygen sensors are installed in both front pipes of the gasoline engine.

The front pipe is bolted to the exhaust manifold (gasoline engine) or turbocharger (turbodiesel). During repair, parts may be replaced separately.

Exhaust system, model 528i
1 — nut
2 — front pipe
3 — catalytic converter
4 — clamp
5 — bolt
6 — auxiliary muffler
7 — crossmember
8 — rubber mount