Auxiliary belt replacement: BMW E60, E64 B50A drive 5.0 (S85B50A)

Step-by-step auxiliary belt replacement for the BMW E60, E64 B50A drive 5.0 (S85B50A): 18 steps. What to remove, in what order, and what to check after.

Workshop procedure for BMW — the exact step sequence and torque figures, straight from real workshop data.

18 steps 1 engine code

🧭 Before you start

Fits: platform codes M5, |, M6

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At removal, mark the direction of rotation; when refitting ensure the drive belt rotates in the same direction

🔧 Engine codes this applies to

S85B50A

📋 Procedure

Preparation and removal

Remove the fan cowling
Remove the compressor drive belt
Remove the screw(s)
Remove the screw(s)
Remove the belt tensioner

S85B50A? Steps differ between engine variants — check this job against your exact car before you commit to it. Check my car — free →

Move the tensioner to the slack position
Remove the ancillary drive belt
Note: At removal, mark the direction of rotation; when refitting ensure the drive belt rotates in the same direction

Installation and checks

Fit the ancillary drive belt
Refit the drive belt tensioner(s)
Refit the screw(s)
Refit the screw(s)
Fit the compressor drive belt
Refit the fan cowling

Other BMW procedures

Who makes these pages, and how

TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.

The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.

Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.

Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com

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Workshop data on this page last updated 20 Sep 2026.