I own a 1997 E320. The right rear window regulator just failed, requiring replacement (out of warranty). In checking through my records, I just discovered that a few years ago I had a similar problem with the left rear window regulator, which was replaced under warranty. Does anyone know whether there is some type of defect in this window regulator? It seems very odd to have 2 separate failures. The car has only 49K miles. The first failure was at 32K miles, the 2nd failure was just now. This little repair set me back over $500 at the local dealer.

 

The rear window regulators in the E-class are a classic case of cost-cutting in the wrong places. The pulleys that the cable for the regulator rides on are a cheap plastic that wears out and breaks prematurely, causing the cable to wind up in the window motor, effectively completely disabling the window. It's not an odd problem, in fact very common. But.......if it's out of warranty, you're going to have to pay for it.

 

Good timing... mine just blew also, and the dealer replaced it for $336.

I was sitting at a red light, and all of a sudden I heard this "wham" explosion-like sound, at the passenger side rear door. I jumped out of the car (at a red light, remember) because I thought somebody had just smashed into me or thrown a rock into my car door. Anyway, I looked around and everything looked fine... confused, I got back into the car and drove
away.

That weekend, I was washing the car and lowered the window. Grind, smash, growl, screech... the window went down, but never came back up. I was able to yank it back up with my hands, but immediately went to the dealer. Replaced in one day, for $336 (1997 e420) . And by the way, the FormulaOne tint was totally unaffected by the regulator failure, or the dealer's repair work.

 

Both rear window regulators have gone out on my 97 E420. One at about 20,000 miles before I purchased the car, and the other a couple of months ago at about 32,000. Most recent repair was covered under Starmark warranty fortunately. This is my first MB and I'm surprised that something so simple would break. Not what I expected.....

The $1,000 I paid for the Starmark has already paid off and I've owned the car since September 2001. Along with the window regulator, a repair to the Xenon lights ran almost a grand by itself. Good investment in my opinion.

 

I wonder why the rear window regulators seem to fail more often than the front ones? Or is this just a coincidence? Maybe the mechanism is different (since the front ones are probably used more often)....or, maybe the rear ones stick after infrequent use and are prone to breaking sooner. Is there a mechanic out there who knows if the the Mercedes front and rear regulators are built the same? Why would the rear ones fail more often?

 

The front regulators are made of metal, with no cheap cables or plastic parts. The rear regulators are made with cables and plastic wheels, to make them more compact to be able to fit in the smaller rear doors. They're completely different parts, and the front regulators should last the life of the car.