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Discussion Starter #2
To OEM or not to OEM?

In my two years of Beast ownership I've had the front door cards off 7-8 times, most of them due to window regulator failure. I've tried one OEM (BMW-branded) and three OE knock-offs (made by Febi) and my experience tells me that OEM lasts much longer.

Of course, the desert climate may have something to do with the OE regulator's short life expectancy, so others may not find much difference between the two.

For me however, the price difference isn't worth the time needed to replace the regulator, nor the hassle of having it fail on you when you need its functionality the most.
 

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Discussion Starter #3
False positives

If your window isn't sliding the way it should, it doesn't necessarily mean that the window regulator has failed. Here's what might have happened instead:


  • the rubber on the guide clamps has perished/cracked/hardened and subsequently lost grip of the window glass. A little fettling can get it to work but the fix tends to be temporary. Since it is difficult to source these window guides separately, typically the most straightforward remedy is to get another window regulator with fresh rubber
  • uneven cable tension, which can be remedied by temporarily pulling out the window motor to reset the tension distribution across the regulator. If this is to blame, you should see the springs re-adjust themselves when the motor is removed
 

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Discussion Starter #4
Failure Modes

So far I have seen the following causes of failure:

  • cable shrinkage, which completely throws off the regulator's "calibration". Window regulators suffering from this will typically work smoothly and then jam at a certain point
  • collapsed spring plastic housings, my guess is they go brittle due to thermal fatigue and snap/crack
  • worn plastic pulleys, which again go brittle due to heat and age
 

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Now this is how a DIY is done. :goldcup::thankyou:
 

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Thanks. I think I'll need to tee this job up. Can anyone confirm if my story fits a failed/failing regulator?

- Currently, the driver's front switch just clicks, w/o any other sounds/vibrations from the window. All other 3 windows work normally from the driver's switch cluster. When I am outside the car and use the press-hold-unlock on key fob, or turn-lock-hold in the driver's keyhole, the other 3 windows move, but not the driver's front.

- Car has been in FL, and I roll down/up the driver's front window to access a keypad to enter/exit a secured garage. The car is on an uphill incline when I enter, if that matters. And that's the first time I sensed a problem.

- I thought I had imagined the switch not responding once before a few weeks ago, but then it continued to work. This time, after a weekend in the garage, it didn't respond, then did, and I was lucky enough for it to quit while rolled up. Now I've stopped messing with it.

- I have never heard any strange sounds from this or any window. They have all seemed to maintain the same smoothness, speed, and operation, until this one gave up the ghost.

- Other: I rarely use the one-touch press of the window switch, but if I do, more often it's one-touch up than down. I rarely ever drive around with my windows down. The sunroof gets the most use of any, and even that's infrequent since it's bloody hot here.
 
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