Ive got a bunch of bmw's and have replaced more regulators on my bmw's than I have spark plugs, brakes, and air filters on any other vehicle I have ever owned.

My money is on the regulator. I have never had a motor go bad on one. It has always been the regulator. I even stock regulators now so I can just pull on from my cache when needed.

All friends and family know not to touch my window switches on my bmw's. They even quote my moto back to me when the subject comes up.

"Its not IF the regulator is going to fail, its a matter of WHEN its going to fail."

Now one thing I did find interesting was I did find a way to stop them from failing all the time FINALLY.

First if you keep the rubber insulation lubricated with something like gummi fledge and such it greatly extends the life of the regulators.

But the solution strangely enough (at least so far) is to tint the windows. The window tint keeps the windows from sticking to the rubber and killing the regulator.

So far at least. The ones I tinted have gone years now with no more regulators.

__________________
Just BMW's - All cars and trucks was two pages long
1994 318is
1997 528i
2000 323i
2001 X5 3.0 auto
2005 X5 3.0 auto
2011 535xi auto
2013 X5 xdrive35 Turbo
More are at my website

Aftermarket E53 Radio Install