E39 M5 / Z8 Vanos
The 1999 - 2003 US and Euro E39 M5 and Z8 (S62) uses a dual vanos for each bank of cylinders making it a fairly complex system. While the vanos units themselves are quite reliable and should last the life of the car, the solenoids can cause various problems which can be mistaken for a vanos failure. While we do offer a rebuild service for the M5 vanos if needed, but most vanos related issues can be addressed by simply repairing or replacing the solenoids. The next few slides offer specific information for the most common M5 Vanos problems and how to address them. We highly recommend keeping a code reader in the glove box to easily troubleshoot any fault codes generated without the need to take it to the dealer. We can help diagnose fault codes for you and determine the best method for resolving the issue to save you from needless or expensive repairs.
Click the slides below for additional information...
There is NO need to touch the 4 set screws on the solenoid cover (if you have the style with set screws). These are preset at the factory and should never need to be adjusted or removed!
Sometimes the solenoids will practically fall out of their sockets and sometimes they will not budge. We don't recommend using pliers to remove the solenoids as you can easily damage the wiring or diodes. There is a lip on each solenoid just under the rubber grommet that it sits in. You can simply use a flat blade screwdriver and gently pry each solenoid up, starting with the 2 lower solenoids, then the 2 upper solenoids. If this does not work install the solenoid cover and all 5 bolts but leave them slightly loose, leaving a ~2mm gap between the solenoid cover and the vanos unit. Start the engine for 3-4 seconds and this should force the solenoids loose using oil pressure inside the vanos. You may get some oil leakage so be prepared!
The rattle can be attributed to the splined gears that fit at the back of the vanos, connecting the vanos to the cam gears. Each splined gear has a bearing assembly inside which allows it to spin freely with the camshaft. These bearing assemblies are designed with a very loose tolerance from the manufacturer, causing them to rattle or resonate at certain RPM's. At DrVanos we modify these bearings to bring the tolerances down for a tighter fit. By reducing the tolerances in the bearing assembly the gears no longer resonate and the diesel rattling is reduced considerably. This is a permanent modification that will last the life of the car.
The removal and installation of the splined gears is a fairly complex procedure and not practical for the average DIY owner but a qualified BMW technician should be able to replace the gears in a few hours. If you are interested in more information about reducing the rattle on your M5 please contact us. We can supply rebuilt gears on a core exchange basis at a very reasonable price.
M5 Vanos Rebuild Service
Send us your M5 vanos units and we can rebuild them with all new Viton and teflon seals, new gaskets and lifetime solenoid O-rings. We can also test and replace any faulty solenoids if needed as well repair damaged solenoid boards, wires, connectors, etc. Replacement solenoids are $400 each with the rebuild service.
Rebuild service starting at $300 each
Solenoid Testing and Repair
Having solenoid issues? Send us your solenoid board and we can test and replace individual solenoids with a quality replacement saving you the cost of a full replacement pack. We can also replace broken connectors and wires, fix damaged boards, and replace missing diodes at a very reasonable price.
Price: $400.00 per individual solenoid
Send your solenoids to us at the address on our contact page. When sending your solenoids in for repair, please include your information in the box and we will contact you with an estimate once they arrive.
For those looking for a ready-to-install solution for the M5 'diesel rattling' noise we offer a rebuild service for the 4 splined gears. The gears are modified to reduce the diesel noise significantly both at startup and at idle.
Price: $300 + $300 refundable core deposit
|Optionally you can send us your gears for the rebuild service.|
Parts and Accessories...
M5 O-Ring Upgrade Kit
These high quality O-Rings will last the life of the car and are a great preventative maintenance upgrade for any model year M5/Z8. The kit includes 16 O-Rings and 2 cover plate gaskets, enough for both vanos units.
Highly recommended for all model years.
Solenoid Cover Gaskets
Replacement solenoid cover plate gaskets are often a forgotten item and are needed whenever removing the solenoid cover plate.
Price: $18 each
Splined gear repair service available! DrVanos offers a replacement spindle service to get you back on the road for a fraction of the cost of a new gear set. Just send your broken gears to us and we can replace the spindle for $45 each. Please note that we do not sell the splined M5 gears outright, but you can buy the spindle for $25 each.