Yes, I have MB brand sunroof grease. And yes, I know that the trick is to apply the thinnest imagineable amount. But no matter how hard I try, after a few weeks the rails are sticky and have attracted dirt.

What I do is clean the rails with alcohol on a paper towel...I get it perfectly clean. Then I apply a very thin coat of grease with my finger. If I used any less, I don't think I'd have complete coverage.

I know I must be doing something wrong. Can anyone help?

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 154k miles
06 E320 CDI "Rutherford", Black on Tan, 172k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver, 142k mi, wastegate conversion

19 Honda CR-V EX 61k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

Yes. Pretend that you don't have a sunroof. Keep a/c working properly.

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2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900

Did you read the FSM procedure for sunroof clean and grease? Its pretty involved. Maybe try following it? Here it is
http://www.ps2cho.net/downloads/MB%20CD/W124/w124CD1/Program/Maintenance/My81/7730.pdf

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What Would Rudolph Do?
1975 300D, 1975 240D, 1985 300SD, 1997 300D, 2005 E320 , 2006 Toyota Prius

i just use singer sewing machine oil--never fails on my car. you're prolly better off following the manual though

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