BMW M50TU / M52 Single VANOS Rebuild Kit — Stage 4

Go beyond rebuilding the VANOS unit with our Stage 4 Single VANOS Rebuild Kit. Designed for BMW M50TU, M52, and US-spec S52 engines, Stage 4 includes everything from our Stage 3 kit plus the additional gaskets, grommets, and VANOS oil feed line needed for a more comprehensive VANOS service.

BMW introduced VANOS variable valve timing in the early 1990s to improve low-end torque, drivability, and engine efficiency. After decades of mileage and heat cycles, the original VANOS piston seals can harden and wear, reducing the unit's ability to properly control camshaft timing. Wear within the VANOS bearing assembly can also create the distinctive metallic rattle these engines are known for.

Common symptoms of a worn Single VANOS unit can include loss of low-end torque, sluggish throttle response, inconsistent power delivery, VANOS-related fault codes, oil leakage, and VANOS rattle.

If the front of your engine sounds like there are marbles or rocks rolling around inside it, there's a good chance you're hearing the infamous VANOS rattle.

Our Stage 4 kit is designed for the owner who wants to tackle the VANOS rebuild and replace several of the common surrounding wear and sealing components at the same time.

Stage 4 Kit Includes:

• 1 PTFE (Teflon) Piston Ring Seal
• 1 FKM (Viton) O-Ring Seal
• 2 Copper VANOS Oil Line Sealing Washers
• Anti-Rattle Bushing Set
  • 1 Anti-Rattle Bushing
  • 2 Anti-Rattle Bearings
• 1 OEM VANOS Sealing Gasket
• Valve Cover Gasket
• Spark Plug Well Gaskets
• 15 Valve Cover Rubber Grommets
• VANOS Oil Feed Line
• Banjo Bolts

Why Choose Stage 4?

Stage 4 is our comprehensive Single VANOS service kit. In addition to rebuilding the internal VANOS components, it allows you to replace several aging parts that are already accessible during the repair.

The valve cover must be removed as part of the VANOS service, making this an ideal time to replace the valve cover gasket, spark plug well gaskets, and rubber sealing grommets rather than reinstalling old, hardened seals.

We've also included a new VANOS oil feed line with banjo bolts. This line supplies pressurized engine oil to the VANOS system and can develop leaks as it ages.

With Stage 4, you can address the VANOS seals, bearing rattle, VANOS mounting gasket, valve cover sealing system, and oil feed line in one service.

Don't Be Fooled by Cheap VANOS Kits

Not all VANOS rebuild kits are created equal. There are cheaper kits available online, but the quality of the seals, bearings, and materials is not the same. There's a reason some kits sell for less than half the price.

We source quality components specifically for these applications and use an OEM VANOS sealing gasket where specified. Stage 4 is designed to give you the parts needed to perform a more complete repair instead of piecing together a kit from multiple sources.

Special Tool Required

A modified 18mm socket is required to disassemble most M50TU/M52 Single VANOS units. We offer the properly modified socket separately at a small additional cost to make the rebuild easier.

Important: Some 1993 Single VANOS units require a modified 17mm socket instead of the 18mm version. Verify your VANOS unit before ordering your tool.

Fitment Guide

This kit is designed for BMW models equipped with M50TU, M52, and US-spec S52 Single VANOS engines. Fitment varies by market and production date.

Important Fitment Note: Because Stage 4 includes a valve cover gasket set, rubber grommets, and VANOS oil feed line, some components can vary by engine, chassis, and production date. Be sure to select the correct vehicle/engine option when ordering.

BMW transitioned several models from Single VANOS M52 engines to Dual VANOS M52TU engines around the 1998–1999 model years. Verify your engine and production date before ordering.

European Z3 M Note: European-market Z3 M models use the S50B32 engine, which has a different Double VANOS system and does not use this M50TU/M52 Single VANOS rebuild kit.

Stage 4: The Comprehensive VANOS Service Kit

Choose Stage 4 when you want to do more than rebuild the VANOS itself. This kit combines the upgraded VANOS seals, anti-rattle components, OEM VANOS gasket, valve cover gasket set, 15 rubber grommets, and VANOS oil feed line with banjo bolts into one convenient package.

Instead of removing the valve cover and VANOS unit only to reinstall decades-old surrounding seals and hardware, Stage 4 gives you the parts to refresh the entire area while you're already in there.

Rebuild it once. Rebuild it right.