Original BMW Twin-Chain Guide Rail for S54-Powered M3, Z3 M Coupe/Roadster, and Z4 M Coupe/Roadster (2001–2008)

This Original BMW timing chain tensioner rail, part number 11-31-7-836-441, is the guide rail that keeps the twin timing chain on its path on the S54 engine in the 2001–2006 BMW M3 and the Z3 M and Z4 M Coupe and Roadster. BMW names it the chain tensioner for the twin chain. It is also called the timing chain guide rail or tensioner rail. The rail weighs 96 grams, is made in Germany, and is sold as a single piece. BMW began production of this version in September 2004.

Original BMW Parts carry a 24-month parts warranty.

Timing chain rails carry a plastic facing that the chain runs against, which quiets the chain and keeps it on its path between the crankshaft and camshaft sprockets. That facing wears over time, and once it wears down to the metal, the result is noise from the timing case and a timing problem. A failing rail commonly shows up as rattling or clattering at startup or idle. Severe wear can let the chain slip, leading to misfires, stalling, or hard starting. This number replaces the earlier 11-31-7-830-557, and BMW rates the change as exchangeable retrospectively, so the newer rail also serves cars that left the factory with the older number. A replacement rail is required when performing a timing service on these engines.

Technical Details

• Manufacturer: BMW
• Part number: 11-31-7-836-441
• BMW part name: chain tensioner, twin chain
• Also known as: timing chain guide rail or tensioner rail
• Supersedes: 11-31-7-830-557, exchangeable retrospectively
• Weight: 96 g (0.2 lb)
• Production start: September 2004
• Sold as: one piece
• Made in Germany
• Warranty: 24 months on Original BMW Parts

Common Questions

What are the signs of a worn tensioner rail?
Rattling or clattering from the timing case at startup or idle is the most common sign. Severe wear can cause misfires, stalling, or hard starting.

My old rail is 11-31-7-830-557. Will this replace it?
Yes. BMW lists this as the replacement and rates it exchangeable retrospectively.

Should I replace this rail during a timing service?
Yes. A replacement guide rail is required when performing a timing service.

Fresh guide rails keep an S54 sounding as crisp as BMW M intended.

Fitment & Compatibility

Use the table below to verify the year and submodel for your build. Send your VIN and PMB Performance will confirm the fit, drawing on more than 20 years in the trade.