Whining Noise From a Super Clean BMW M3 E36 Dinan Supercharger

There can be several reasons for a whining noise from under the hood. On a particular E36 BMW M3 that recently came into our shop, the Dinan supercharger was one of those reasons.

A supercharger or “blower” is a belt-driven pump that forces air into the engine under pressure known for whistling or whining. This, however, was no blower whistle. Instead, the problem was with the power steering rack. In this blog post, we’ll tell you what we did to solve it. We’ll also share some tips on power steering system maintenance. First though, a little more about the car itself.

A Special M3

For many enthusiasts, the E36 BMW M3 is the car they dream of. They were built between 1994 and 1999, and unlike earlier M3’s, were available as a sedan. For many buyers, this made it an efficient performance car.

The “whiner” that came into the EurAuto shop in Plano, TX, was a beautifully maintained example. Making it particularly noteworthy was the supercharger, as mentioned above. Dinan is a company that has long specialized in aftermarket performance parts for BMWs, so when you see the Dinan name under the hood, you know the job has been done right.

A Whining Steering Rack

One of the common reasons for whining is a worn power steering pump, especially if the system is low on fluid. That wasn’t the case here, though, perhaps because the owner was meticulous about maintenance. Instead, the problem traced back to the rack itself.

Steering racks can develop problems as they age, particularly leaking seals. This shows up as drips on your garage floor and can pool in the tie rod boots. You may also notice increased play in your usually very sharp BMW steering.

We were told there had been an attempt to bleed the power steering system (which would remove any trapped air bubbles) on this car, but the whining was still there. This meant it was time for a steering rack replacement.

Swapping Out the Rack

On the E36 steering rack, replacement isn’t complicated. You need the car in the air, and you have to separate the tie rod ends from the wheel hubs, which can be awkward. Then it’s just a case of draining the fluid, disconnecting the hoses, and removing the rack itself.

Installation of the new rack is, as the handbooks say, the reverse procedure. Here we installed an E46 rack which provides an upgrade in steering feel. (It also requires new tie rod ends to suit.) Then with new hoses connected and the reservoir refilled, all that’s left is to bleed the system.

Incidentally, the E46 was the generation of the 3-Series that followed the E36. To date, there have been seven generations of 3-Series BMW.

Power Steering System Maintenance

Here’s an interesting factoid: the E36 doesn’t use power steering fluid. Instead, the engineers in Germany decided to use automatic transmission fluid or ATF. Like engine oil and brake fluid, ATF ages over time and eventually needs replacing. If you don’t know when the fluid in your car was last changed, it might be time to ask about auto repair in Plano, TX!

Contact EurAuto Today

Along with the fluid, it’s good practice to replace the power steering hoses periodically. Like all rubber hoses, they age and gradually lose flexibility. Eventually, they’ll start to leak. If you notice you have to top up the power steering reservoir every few months, it might signify that new hoses are required! If so, we’ll be pleased to help. Give us a call at 214-552-4194 to schedule an appointment today!