evanblack00

So, when you order an AMG exterior, your car comes with RFT tires. Can you convert them to conventional by simply buying a set of new tires? Or is it more complicated than that?

ua549

You'll have to have the RFT's removed by a shop with RFT capabilities. After that conventional tires can be serviced by any shop.

ProtonCharlie

physically, it's not a problem. The problem is many tire shops will refuse to do it because they fear the bloodsucking lawyers. It is a liability to replace with something lower than the door placard.

ProtonCharlie

Removing and installing run flats is really no different than any other tire. What most shops will not do is repair runflats. Even with the capability, it's usually not the best idea.

ProtonCharlie

Double post*

c4004matic

Yes and yes. The E class has extended mobility not runflats. EMT's can be serviced anywhere. You will have to buy a tire fix kit or a spare.

threeMBs

What is the difference? Aren't EMT and RF are the same, but just called differently (both can be used at zero pressure at 50mph upto 50 miles)?

jweek

From Tirerack:

"Tires branded with MOExtended or MOE on their sidewalls identify them as being specifically tuned for Mercedes-Benz vehicles. The Extended portion of the name identifies they feature run-flat-like tire characteristics by offering temporary extended mobility. However since they don't meet all of the International Organization for Standardization (ISO) run-flat tire operating limits under all permitted vehicle loads, they cannot be branded as run-flat tires.

...traditional ISO run-flat tires are rated to provide temporary mobility for up to 50 miles (80 km) at up to 50 mph (80 km/h) for all permitted loads after the vehicle's tire pressure monitoring system (TPMS) alerts the driver of significant tire pressure loss.

While the same speeds are permitted 50 mph (80 km/h), MOExtended tires are designed to provide temporary extended mobility on a fully loaded vehicle for up to 20 miles (30 km) and on a lightly loaded vehicle of up to 50 miles (80 km) after the vehicle's tire pressure monitoring system (TPMS) alerts the driver of significant tire pressure loss."

c4004matic

Correct. In addition some RFT's like the michellin PAX, have special rims and support donut which needed special machines to service. EMTs are essentially regular tires with a stronger sidewall. The reason they cannot be fixed if punctured is simple, once they are used in a low pressure state the sidewall is considered "ruined".
The e43 on 20's is equipped with high performance summer tires so Ill keep them till they wear out, after they are done its back to Michelin pilot super sport for me. There is simply no better street ultrahigh performance tire, an additional bonus is that they last almost twice as long as other tires in their category. It offers track worthy performance and road manners that rival some all season tires, definitely worth a few bucks.

threeMBs

Are you planning to carry a full size (about 27" diameter) spare in the trunk? Since there's no room for spare under the floor, with full spare, trunk will have hardly much room left. E43 with 20" MO tires should come with excellent newer generation PZeros "run flats".

ua549

Continental makes a T145/60R20 compact spare with a 26.7" diameter. I'm looking for a matching steel wheel.

Mike26Mercedes

My 2017 E Class Luxury trim with 17' tires are Pirelli Run Flat. It is molded into the sidewall, RUN FLAT.

c4004matic

I was hoping it would fit in the trunk hole which looks pretty large to me. The spare just needs to be a 225 18 tire. Once you remove all the stuff in there it its a very large hole. Of course I havent tried it yet. When I get my car I will let you know. Again the manual has a whole section on hanging a tire and using a jack so there has to be areas where they stick a tire in there.

threeMBs

Mercedes' MOE is run flat.

Following is OEM on 2017 W213 E-class with 20s:

"Pirelli P Zero Run Flat (PZ4) tires are Max Performance Summer tires derived from Pirelli's Formula 1 experience and developed for use as Original Equipment on the BMW 7 Series, Mercedes-Benz E-Class and MINI Clubman, with select replacement tire sizes also included in the lineup."

Following is OEM on 2013-2017 R231 SL-class with 19s:

"The ContiSportContact 5P SSR (Self Supporting Runflat) is Continental Tire's Max Performance Summer run-flat tire designed to provide temporary extended mobility in case of complete air loss due to a puncture."

As can be see, "extended mobility" is used with "run flat" in the same sentence.

I just took off these SSR 5P from my SL. Tire's bead is like a piece of wood.

c4004matic

Indeed they are, but again, tire manufacturers do separate them depending on their capacities. MB uses a variety of summer tires on their 20 in rims, for example, one that is missing on your list is Yokohama.


https://www.tirerack.com/tires/tiret...jsp?techid=234&
https://www.tirerack.com/tires/tiret....jsp?techid=56


As far as spares go, the width of the tire is unimportant, the overall diameter is, ergo, as long as the rim clears the brakes (for the E class that's 17 inches) you can use any tire you want as long as the overall diameter is more or less the same (+/-5 %)