So had my first flat last weekend. On the Atlantic City Expressway. Noticed the pressure drop to 35psi on the front left. I caught it before the warning came on. By the time I pulled off about 5 minutes later, it was around 29psi. The warning came on flashing red at about 30 psi, fwiw. Baseline setting was 41psi. I made it to a Wawa parking lot and managed to use the tire sealant in the trunk with the compressor. Pumped it to 45psi. Some white stuff bubbled out around the screw I had picked up. I made it to Atlantic City and then the 50 miles home later that evening with 100% pressure holding.

I called my tire dealer the next day and they ordered me a new Michelin PS4. I had swapped my Pirellis for the Michelins right when I got the car. I opted out of the ludicrously expensive Mercedes Wheel and TIre insurance and instead bought four new tires and spent about $50 for road hazard coverage! Plus I got to keep my Pirellis to throw on before I return the lease! The tire was ordered Monday and on Wednesday at lunch I had them install it. They did not charge me anything. I did tip the manager and the worker who did the tire. I also bought lunch (Popeyes ) for them, as well as another guy in the shop. Total bill $35....

Reason for the post..... I was really surprised to see the inside of the tire with the sealant. It remained a milky liquid. It does not dry up or harden and it is not sticky, nor did it seem to react with the rubber. Looks like it could have been rinsed out and the tire cleaned for a patch for those cheap b@stards among us! Got a new tire so no matter.....

Lastly, I called my dealer to get a new replacement sealant cannister and the parts guy told me that they have NEVER sold a single one. They had to order it in and it took two days. $73.95 fwiw. I confirmed on Thursday last week when I picked it up that they had truly never sold a replacement cannister. Hard to believe. This is a large northeast dealership with a bunch of AMGs on the lot. I am shocked..... Crazy!!!

Here are the pics.



Torx head screw


That is a shop rag in the milky sealant


The culprit

 

Thanks, that's good to know.

I've never used a tire sealant on a car tire before. I carry plugs in my Jeep and have a compressor built in to my winch, but thankfully haven't needed to try them yet.

On bicycles and motorcycles I've had good luck with Slime. Picked up a bunch of punctures once running over some thorns on the mountain bike. The few patches that I had wouldn't do the trick. Another rider with me had Slime in their tires and ran over the same patch. We checked their tires and sure enough they were full of thorns but were holding air fine.

Started running slime on both the mountain bike and the dirt bikes and never had another flat.

Given that experience, I've been hopeful that the tire sealant would work on the E63 just like it has for you - so that's great news!

 

I have patched tires with sealant in them before, as you say if you clean them properly and apply the patch properly, it will work just fine.

Very few people use the sealant, most just have the car taken to get a new tire.

 

I have heard to never use them because the clean-up afterward will be a mess. I have read it will react with wheel metal and mess up the tpms. Not sure if true on what I have heard or read.

Does anyone have any experience with aftermarket ones?...Maybe they are the same?

 

I used the tire sealant once (on my past bmw). It was not effective at all, as a matter of fact, it made a real sticky mess inside the wheel which the tire shop spent extra time to have that mess cleaned up before the new tire can be put on.

Perhaps, MB is using different tire sealant brand as compared to my experience. If I encounter another flat tire, I would simply call it in and get roadside assistance, if the puncture is big enough.

 

Many of the sealants are advertised as TMPS safe, but some of them do use very harsh chemicals and can cause issues.