SL/R230: Trunk leak SOLVED, no replacement
Thread Starter
Junior Member
Joined: Jun 2014
Posts: 49
Likes: 3
SL600, S550, GLS450
Trunk leak SOLVED, no replacement
Leaky trunk seal is a known issue for the R230, for me it has always leaked where the seal fold together on each side (right over the rear wheel wells inside the trunk).
I previous tried cleaning it with no success, I have also tried rubber 'restoring' products, no luck. I also ready that some people have had them replaced only for them to start leaking again shortly after. I have always put a towel or dog training pad, sometimes those even get so wet they start to soak through after a heavy rain.
I tried something that has so far worked awesome. It has been 95% effective, as every once and a while there is couple drips in the trunk after long heavy rain, but almost 100% improvement and held up over the last 4-5 months with 1 application.
I used marine grease (same stuff I use on boat trailer bearings) and rub it it, then come back with a clean towel to wipe off the excess. There isn't any buildup, just the residue you get from wiping a heavy grease over a rubber gasket. Makes the gasket look/feel new. It is not enough to be sticky/gooey and visible as that would likely attract dirt and debris. Non-marine grease would probably work too, that is just what I tried and worked for me the first time.
Maybe others have suggested this in the past, I just havent come across it yet. Hope this helps!
I previous tried cleaning it with no success, I have also tried rubber 'restoring' products, no luck. I also ready that some people have had them replaced only for them to start leaking again shortly after. I have always put a towel or dog training pad, sometimes those even get so wet they start to soak through after a heavy rain.
I tried something that has so far worked awesome. It has been 95% effective, as every once and a while there is couple drips in the trunk after long heavy rain, but almost 100% improvement and held up over the last 4-5 months with 1 application.
I used marine grease (same stuff I use on boat trailer bearings) and rub it it, then come back with a clean towel to wipe off the excess. There isn't any buildup, just the residue you get from wiping a heavy grease over a rubber gasket. Makes the gasket look/feel new. It is not enough to be sticky/gooey and visible as that would likely attract dirt and debris. Non-marine grease would probably work too, that is just what I tried and worked for me the first time.
Maybe others have suggested this in the past, I just havent come across it yet. Hope this helps!
Junior Member
Joined: May 2024
Posts: 60
Likes: 12
From: The Sunshine State
SL500
Many years ago (1960a) GM recommended rubbing the exterior seals on their cars with Dow Corning DC7 silicone grease and then rubbing it in. I know people that did that religiously and the seals in their cars always lasted for decades. What to put on seals has long been a topic on various car cleaning and restoration forums and the general consensus has been to use some kind of silicone grease and NOT to use anything that has petroleum in it. Many of the silicone sprays also contain petroleum and most knowledgeable people avoid them for that reason. Many people recommend Gummi Pflege but the stuff is stupidly expensive.
I just go the MB so I tried it on that yet but I have a tube of Dow Corning 111 grease and I've used that on other cars and I've never had any cause to complain. I've used it around taillights and on the 3rd brake light on my F-150 which don't have actual seals and are very leak prone and the silicone grease seems to plug up the cracks and prevents any water intrusion.
What ever you choose, I would avoid anything with petroleum in it. And I'd be very wary of any "restorer" product that makes the seals swell. I think that it will eventually make them swell and crumble.
I just bought a 2004 SL500 and from the records that I've been able to get it has always been maintained by a M-B dealership. I don't know what they use or if they even treated the seals with anything but all of the seals in it are in great condition and there are no leaks that I've found. Does anyone know if the M-B shops normally apply anything to the seals or what they use?
I just go the MB so I tried it on that yet but I have a tube of Dow Corning 111 grease and I've used that on other cars and I've never had any cause to complain. I've used it around taillights and on the 3rd brake light on my F-150 which don't have actual seals and are very leak prone and the silicone grease seems to plug up the cracks and prevents any water intrusion.
What ever you choose, I would avoid anything with petroleum in it. And I'd be very wary of any "restorer" product that makes the seals swell. I think that it will eventually make them swell and crumble.
I just bought a 2004 SL500 and from the records that I've been able to get it has always been maintained by a M-B dealership. I don't know what they use or if they even treated the seals with anything but all of the seals in it are in great condition and there are no leaks that I've found. Does anyone know if the M-B shops normally apply anything to the seals or what they use?
Banned
Joined: May 2023
Posts: 209
Likes: 3
just looking
Leaky trunk seal is a known issue for the R230, for me it has always leaked where the seal fold together on each side (right over the rear wheel wells inside the trunk).
I previous tried cleaning it with no success, I have also tried rubber 'restoring' products, no luck. I also ready that some people have had them replaced only for them to start leaking again shortly after. I have always put a towel or dog training pad, sometimes those even get so wet they start to soak through after a heavy rain.
I tried something that has so far worked awesome. It has been 95% effective, as every once and a while there is couple drips in the trunk after long heavy rain, but almost 100% improvement and held up over the last 4-5 months with 1 application.
I used marine grease (same stuff I use on boat trailer bearings) and rub it it, then come back with a clean towel to wipe off the excess. There isn't any buildup, just the residue you get from wiping a heavy grease over a rubber gasket. Makes the gasket look/feel new Jewel Cars Gatwick. It is not enough to be sticky/gooey and visible as that would likely attract dirt and debris. Non-marine grease would probably work too, that is just what I tried and worked for me the first time.
Maybe others have suggested this in the past, I just havent come across it yet. Hope this helps!
I previous tried cleaning it with no success, I have also tried rubber 'restoring' products, no luck. I also ready that some people have had them replaced only for them to start leaking again shortly after. I have always put a towel or dog training pad, sometimes those even get so wet they start to soak through after a heavy rain.
I tried something that has so far worked awesome. It has been 95% effective, as every once and a while there is couple drips in the trunk after long heavy rain, but almost 100% improvement and held up over the last 4-5 months with 1 application.
I used marine grease (same stuff I use on boat trailer bearings) and rub it it, then come back with a clean towel to wipe off the excess. There isn't any buildup, just the residue you get from wiping a heavy grease over a rubber gasket. Makes the gasket look/feel new Jewel Cars Gatwick. It is not enough to be sticky/gooey and visible as that would likely attract dirt and debris. Non-marine grease would probably work too, that is just what I tried and worked for me the first time.
Maybe others have suggested this in the past, I just havent come across it yet. Hope this helps!
MBWorld Fanatic!
Joined: Mar 2018
Posts: 1,442
Likes: 260
From: Netherlands
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
MB sells very small bottels of rebranded Krytox by Chemours for this. https://www.krytox.com/en/products/automotive
VW does the same, a bit less expensive, for its notoriously leaky Eos convertible.
Krytox works fantastic, the small bottle will be enough for multiple applications. Agree with above to clean your seals first (white paper, luke warm water, nothing else, be amazed at the amount of filth coming off). It stops creaks as well.
VW does the same, a bit less expensive, for its notoriously leaky Eos convertible.
Krytox works fantastic, the small bottle will be enough for multiple applications. Agree with above to clean your seals first (white paper, luke warm water, nothing else, be amazed at the amount of filth coming off). It stops creaks as well.
