Eddot

Contemplating going from my 19" staggered OEM P7 run flats to a better mileage Touring non run flat and a decent price point like the General G Max or the Kuhmo Majesty 9, both highly rated. I'm not going to carry a spare and rarely travel more than 60-70 mi. from home. I have AAA 100 mi. towing so I can flat bed back home and fix a puncture. Question is, would it be advisable to carry and use the New... Slime Smart Spair Plus Flat Tire Repair Kit in an emergency. This one goes right through your valve stem and does not effect your TPS...so they say. Videos show cleaning from inside tire is a little tedious but not bad and patch repairs can then be done, though I would probably Fiber Plug and be done with it. Give me some input and also on the tires. Rears are going to need replaced at 12000 mi. Does this sound right or would Michelin or Continental run-flats have worn longer?

superpop

These cars like to eat tires, especially the staggered set ups as you cannot rotate. I plan on going non RFT on my next set. I just carry a patch kit for emergencies. No interest in the donut spare as you can only go 50MPH on them. If anything I may get a 5th wheel to match my set with a new tire. A bit bigger but it would be swap and go.

Eddot

I do carry an AirHawk tire inflator in all my cars as a precaution for a Low Pressure warning. Dealer is telling me that 12-15k mi. is proper for rear tires. His advice is replace all 4 with Mich. run flats for only $1800. "its an S class, why would you not want the best" To me, if wear is going to be the same, I'd rather go with a non run set for under $800 and take my chances. Thats the way I went with my Z4 2 years ago and there fine.

joeyb1000

I carry a plug kit, but the injectable slime isa good substitute. Non-run flats are not prone to catastrophic failure; so for most leaks the TPMS will give you time to get to a place to fix it.

Quadrobenz

Try not to overthink this. None of the AMG V8's or V12's use run-flats nor do they have spares. An inflator pump and large can of goo is provided. Never used them. In over 300k miles I have never had a disabling puncture. Picked up a few coated drywall screws over the years, some did not leak at all, some would loose about a pound/week. I did break a wheel on a road hazard on an SL600 that had a spare. An RFT would not have helped. I drove it on the flat for 5 miles to a tire dealer.
Ironically the most serious puncture I ever had was in Pittsburgh three years ago when I drove the S65 back to visit them. The low pressure warning came on as I was on I70 westbound crossing into Ohio. Kept going while watching the tire pressure. The pressure was not dropping below the 33lb warning. Put air in the tire when I stopped for gas and all was well for the rest of the day, the tire held pressure as long as it was hot. I filled the tire to 46psi when I stopped for the night, there was a humongous nail in the tire. The tire pressure dropped about 7lb overnight when it cooled off. Showed 38lb cold in the morning, heated to 42 on the interstate and never changed the entire day so I drove it with the nail all the way home to SoCal. Since I had purchased the tires at the dealer they just put on two new rear tires, no cost, under their road hazard warranty.

GSoprano

Run flats for my 2015 s550 did nothing for me to save the money I just went with non run flats , I was told by local dealer that runlets are actually not good because they hit pot holes harder due the pressure Inside the tire

DaveW68

I have these tires and they are the quietest and smoothest tires I've ever had on any car. They are very stable in the rain and stick like glue to the road.

And then keep this in your trunk for an emergency if it should ever arise.

Popo Here

They hit potholes harder because of a very stiff side wall not pressure. The pressure is the same with or without run flats.

Don't overthink this one but just go with the tire of your choice. You'll be fine

Popo Here

The one time those run flats saved me

Tom in Austin

I drive fewer miles than most people and have had, I think, two flat tires over the past 10 years. Fortunately, both were close to home. Have had several smaller punctures where a tire lost air and had to be repaired or replaced. In nearly 50 years of driving I've never had an incident that damaged a wheel to the point that I couldn't continue driving on it.

Calculated risk being without a spare and relying on a 'slime kit' and inflator. I just hope if I get a flat that doesn't respond to slime that I can find somebody nearby with a 245/45/19 tire on hand.

Fred2

If every motorcyclist can go for a ride with no spare, I guess I can too.

I carry these in the cars for emergencies.

Fred2

How fast did that one leak out?
With how the hex is worn on an angle, it looks like that one was in there for a while.

SilverArrow44

I have non-run flat tires and I upgraded to the Mercedes Tirefit (fancy Slime system). However for longer road trips, I purchased a full size spare at Discount Tire that I toss in the trunk and remove when I return home. Of course I also purchased a Mercedes jack kit as well that remains in the car full-time.

In hindsight, I think buying the full-size spare may have been unnecessary. My 222 was the first car I owned that didn't have a full-size spare and it freaked me out. I started running all these worst case scenarios in my head, so I scared myself into buying the spare. To his credit, the sales associate at Discount tried to talk me out of it. He pointed out that the spare would take up most of the trunk space (it does) and that road side assistance and the Tirefit kit, should be all I need. After driving 2 weeks with the spare and realizing how little room was left in the trunk, I decided to leave it in my garage and only use it for extended trips. And if I'm taking more that a bag or two, I find that I don't have room for the spare!

bkdc

I am a belts and suspenders kind of buy and I carry the small spare in the trunk. A hassle but worth peace of mind.
The Pirelli run flats that came with my S-class lasted 11K miles (unusual wear at the tire shoulder despite correct alignment). Michelin Pilot Sport AS 3+ has gone 22K miles with about 40% tread left with even wear across the entire tire.
There is something about the stiffness of the runflats that leads to premature wear at the shoulders.
It is highly unlikely you will encounter a blow-out. The most likely scenario is that you get a slow bleed from a nail or screw. And a portable 12V pump will probably inflate you enough to get yourself home even if you don't carry a spare.

Mitch Alsup

I had a #8 or #10 wood screw in a tire one time, but since the air was leaking at a rate where I only had to fill the tire once a month, I just ran on the tire as it was until the tires were ready to be replaced.