Manufactured from 1999-2006, the BMW e46 3-series is still popular among Bimmer enthusiasts despite one common defect: the front and rear window regulators are known to malfunction. While this problem is more of a nuisance than an actual danger, it is important to find a qualified BMW mechanic to replace the faulty part.
There is debate on whether the window regulators are failing due to poor design, or simply wear and tear. Most likely it’s a combination of the two. The window regulators are constructed with thin cables and plastic pulleys, which means they could wear out over time. And with so many e46 3-series still on the road, these regulators have seen their fair share of abuse.
It takes diligent maintenance to keep the window regulators from failing, but even that doesn’t guarantee they will never fail. Keep the window guides greased and aligned so there is no extra pressure put on the regulator. Also check for loose or damaged tracks, clips or anything that might inhibit the smooth motion of the window. If you window shakes or rattles while driving or shutting the door, you will want to have a qualified mechanic re-align the guides or tracks to help prevent window regulator failure.
There are several how-to videos on the Internet describing how to replace an e46 window regulator, but this is a pretty technical fix, so we encourage you to find an experienced mechanic. It is an invasive procedure that could affect other mechanics within the door and window, so it would be wise to contact an independent, qualified BMW repair shop to replace this regulator with an OEM part.
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