The hardest part is getting the seal and trim over the glass without breaking it. Once you have it assembled use plastic coated clothesline or wire. Lube it up good with dish soap , windex or silicone. Spend some time making sure you have it centered (very important) and start at the bottom, making sure it is seated well down along the pinchweld. You can shift it around a little as you work to keep it centered if you keep it lubed. Honestly, I have done 2 W123 rears and a W116 and didn't have any issues with aftermarket seals. This will take you all day for your first one- by the time you do your 5th you get it down to 2 hrs.

Rick

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80 300SD (129k mi) 82 240D stick (193k mi)77 240D auto - stick to be (153k mi) 85 380SL (145k mi) 89 BMW 535i 82 Diesel Rabbit Pickup (374k mi) 91 Jetta IDI Diesel (155k mi) 81 VW Rabbit Convertible Diesel 70 Triumph Spitfire Mk III (63kmi)66 Triumph TR4a IRS (90k mi)67 Ford F-100 (??)

Always remember - A good glass man doesn't even OWN a screwdriver.

SteveM.

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'93 190E/D 2.5 Turbodiesel 5-speed (daily driver)
'87 190D 2.5 Turbo rustbucket - parts car
'84 Dodge Rampage diesel - Land Speed Record Holder
'13 Ram 2500 Diesel
'05 Toyota 4Runner

The seal goes on the window, then the trim goes in the seal, THEN the whole unit gets pulled in place with a rope.

It sounds like you were trying to get the lock trim in place after the window was in the car. If you need to hammer on anything while doing this, something isn't right ... use more windex to keep everything well lubed.

Here's the thread jt20 was referring to. It's for my quarter window which is different as far as the lock trim (plus no curved glass), but the rope technique is the same.
http://www.peachparts.com/shopforum/diesel-discussion/201820-300td-quarter-window-removal-w-pics-post1937709.html?posted=1#post1937709

I also recommend only using OE seals. They cost a bit more, but save you time and trouble. Plus a proper fit means it requires less sealant to eliminate leaks.

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Chad
2006 Nissan Pathfinder LE
1998 Acura 3.0 CL
OBK#44
"Pleasure in the job puts perfection in the work." - Aristotle (384-322 B.C.)

SOLD
1985 300TD - Red Dragon
1986 300SDL - Coda
1991 - 300TE
1995 - E320
1985 300CD - Gladys

This is exactly right. I tried to get the trim in after installing the window. All I accomplished is bending the trim. I ended up taking out the whole thing and redoing it with junkyard donor trim.

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For Sale: 1982 MB 300TD
1995 Chevrolet Suburban 6.5TD

Sold: 1980 IH Scout Traveler- Nissan SD33T Diesel

X2, thats how it works on the W126 to. Than wrap some very strong string around the seal and put it in.

OE seals are the only ones worth buying, aftermarket are junk.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Lots of dish washing detergent,in the channel with the rope,on the flange,on the seal its messy but it works.Just in case you didnt get it at the beginning,LOTS of dish washing detergent! Don

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Red Green "This is only temporary,Unless it works!"

97 E300D 157000 miles
87 300TD ?141k? miles

I took my 85 300SD to Safelight two weeks ago for a $280. rear window replacement. They had the incorrect glass three times so far and tell me that the window is not available except from MB for $950. + and now I have a car without a rear glass and I am pissed.

Ditch the 3-M and go with the soft stuff that MB recommends then use a ratchet strap around the C post to hold the glass in contact with the frame. Ease the gasket in with lots of soap or GO-JO and keep pushing it into position side to side. do not hit it and if you get frustrated go away for a while and take a breather.

Good luck and wish me the same
Robert

Take the NEW window, seal, and all to Safelite and pay them to install it! pain the wallet, but better than pain in the A$$ and another broken windshield!

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1986 Euro 500SEC "RUF" 9:1CR, "Rose"
1985 Euro 500SEC Cabriolet AMG Widebody
1982 Euro 500SEL "Blue"
2001 Texas Heeler (Aussie/Queensland X) "Sulphie",
2012 Queensland Red Heeler "Squeak"
Best dogs I've ever had.

Used Safelite to replace my windshield, 96 e300d, and was impressed with the speed and quality of their work. Forty five minutes...start to finish, and it looked like they never even touched the car. All decals removed from old windshield and installed on the new one. Cost $235 installed, using their own manufactured glass. Good luck

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96 E300d