Alan Smithee

I have. Have you? Note that I said modern car...we are on the W213 forum...all of the car's safety systems will prevent loss of control. It is you JTK44 posting dis-information and scaremongering. Enjoy your runflats!

The G Man

Are you implying that your stability system will stabilized your car during a high speed conventional tire blowout? Do you think the stability system can compensate for the lost of 3 to 4 inches of sidewall? Even if you do manage to steer your car to the side of the highway, then what, wait an hour on the side of the highway for road side assist? take the risk and change the tire yourself with cars speeding by you at 65 mph? Drive on your rims to the nearest exit?

Alan Smithee

Absolutely. Had a blowout at 80 MPH in a fully loaded E70 X5 some years ago, and it was a complete non-event. Changed the tire on the side of the highway with the optional spare and we were on our way in 15-20 min. Prior to that had a blowout in the rain at speed on the freeway in a 535i, and there was no drama then, either. Changed the tire in the emergency lane of I-5 and was on my way. In both situations I was over 100 miles from home, the X5 tire was not in stock anywhere in So Cal, and the 535i flat was late on a Sunday night. Runflats without a spare would have stranded me in both situations…nothing ‘safe’ about that.

The G Man

With all due respect, I dont have a need or the desire to take the risk of changing a tire on a highway these days. In the old days, runflats were hard to find in stock, not anymore. High speed blowout and breakdown lane accidents are responsible for many deaths each year on American highway. Both of your blowout incidents could have been safer with runflats. Many runflat owners carry a air compressor, slime, plug kit or even a spare when they go to remote areas.

The following article kind of sums up the history of runflats. Manufacturers’ interest in runflats stems from weight saving, cost saving, space saving and safety. It also talk about how runflats have improved over the years.

https://www.autoblog.com/2011/06/18/...ng-spare-tire/

JTK44

Just checked BMW 5 series: The 5 series come with RF tires: There is a $150 option that includes a space saver spare, jack and tools. As I posted above, this would be my choice. It is a shame that Mercedes does not offer this option. There is so much space in the trunk well that I am sure if MB wanted to it could make the spare fit - just as BMW does.

bishop64

This article was written on 2011. I bet run-flats have further been improved in the past 11 years too.

The G Man

I agree, runflats have gotten better in handling, road noise and ride quality, the 1st production car with runflats was a Porsche 959 in 1987. BMW made runflat standard in most of their cars starting in 2003 with the Z4 and the 5 series. I remembered the older runflats on my 5 series would be very noisy and did not handle well. Handling and road noise has much improve but the ride quality is still an area with the smallest gain, the ride has gotten better but still not as good as the ride quality of a conventional tire.

Mac Jones 55

I understand the tire change aversion, and why this is the reason, but it comes down to the actual user; are you feeble, and unwilling to deal with leaks? I have those kits, the battery powered air compressor (that works very well), the tools: wrenches, sockets, triangles and flares, flashlight with stand, padded tarps, and soon a spare with case, and a jack.

So I’m prepared at least. If you don’t have those things, and just haven’t given it any thought, stick with RF. Frankly, I’d rather change a tire, bring my damaged tire to my guy, and have him patch it for $20 in about five minutes, or better yet, patch it myself (which I haven’t tried yet, but I have the kit). Good as new. Also, maybe it depends on the weather a bit also, and so where you live.

I’m thinking about this now, and will probably do the swap just out of curiosity at this point. When I do I will report back

PGH E450

you’re missing an LED headlamp!

The G Man

Tire rack did a snow performance test for the Bridgestone Driveguard vs Pirelli P7 runflats a while ago and the Pirelli came out ahead.

Mac Jones 55

Modernspare sells a kit. Looks like a safe alternative. Any users here? I’m wondering about warranty and fit. It’s an unknown going with a nonOEM spare. Any ideas?

comes with a jack, bag, and some wrenches. I’m thinking OEM in this case isn’t necessary. But I don’t know

TennesseeZ4

I will add to the Pirelli tire acceptance. I have never been a run flat fan, having Continentals, Goodyears, on BMW Z4, SL550 R231, E350, E450 A238; in every case we changed them over to Michelins. When we got our current W213 wagon with the 18" Pirelli P7 runflats, I was determined to go to the 19" wheels and Michelin non runflats. Having put several thousand miles on the Pirelli 18", I have come to accept and enjoy the ride quality of the tires; so yes runflats have improved. Just returned from a two week trip into Florida, put about 2K miles on the car in all kinds of conditions, and the car never put a tread wrong. Also averaged 30.5 mpg at an average speed of 72 mph; the car continues to impress, as do the tires.

Mac Jones 55

Ok so Pirellis are good. My other question is the logic of using RF on long trips, going through rural areas. With regular tires, no problem. RF failure entails what? Makes no sense. Also, if the tire is badly damaged you don’t have a spare, at least most people don’t. I would not drive on a badly damaged tire, RF or not. Worse, apparently MB will guide you through driving out of it on a badly damaged RF which is crazy. At least that’s what I’ve been reading here.

just trying to get a grip on this confusing subject ( confusing to me at least). Where I’m at now is believing the proliferation of RF is partly a trend, and partly the result of studies on user behavior, customer support experience, and other things. You would think they would give you a choice.

but I won’t know until I do this swap. I can always change my mind. Fortunately, they still make regular tires

JTK44

I too have the Pirelli P7 RF MOE on my 2019 E450 with stock 18" wheels: I agree 100%: the ride is superb and in all conditions including ice and snow when I go skiing in Vermont. On long trips I also average more than 30 mpg: :Here is a "cheat sheet": I do not drive my car hard, never accelerate hard and on the highway set the cruise control between 72 and 80 mph: I have always used regular gas with no ill effects. Have over 25,000 miles on the car.

The G Man

I also have the Pirelli P7 runflat, they are nice touring tires, average in snow, the Continental runflats are better in the snow in my opinion. I also had Pirelli P7 conventional tires on my Audi S5, I know the suspensions are different between the E300 and the S5, but the S5 with conventional tires ride stiffer than the E300. My experience from my BMW days of switching out runflats with conventional tires is that it made a difference in ride quality. Handling not so much but with conventional tires, I got less sidewall bubbles. The bad part about changing to conventional tires is the compact tire spare taking up half of the space in my trunk.