Run Flat Tires / Modern Spare Company

[RNajarian]

DISCLAIMER: I have no financial interest in this product.

I recently upgraded my daily driver from a 2012 C350 Coupe (308 HP) to a 2022 E450 Coupe (368 HP with mild hybrid drive.)

It’s a great car but with many new cars it has run flats. I am new to run flats and am not comfortable with the idea of not having a spare.

I came across a company that sells a replacement spare tire set up, complete with all the tools and a convenient carrying case.

https://modernspare.com/product/2017-2023-mercedes-e-class-br-213-spare-tire-kit-options/



Does anyone have any experience with this product? The spare is 18” and is apparently compatible with my 20” tire.

Thanks

[MMARSH]

I bought that setup for our Teslas for when we go on trips out of town. One setup works for both cars. In about three years we have never had to use it. It's kinda expensive, but it makes me feel better knowing I have it in the trunk when traveling outside the metro area.

It's an 18 in wheel and works on my 21 inch wheels and my wife's 19 inch wheels. The wheel in a bag makes it convenient to move between cars.

[RNajarian]

Thanks Michael,

The wife has an E350 with run flats. I’m thinking the spare could be used for both cars just like your Teslas.

Rgn

[Icemaster]

Driving a 2018 GLC300, OEM with run-flats that absolutely wrecked the comfort and ride.

Ebay. Found multiple stories on the MB forums where folks successfully added OEM toolkits and a comparable, temporary spare tire they sourced from a dismantler or OEM reseller for about a third that cost total.

I did the same, took about 15 minutes of searching.

Not your original question, but as soon as humanly possible - ditch those POS run-flats. Mine lasted 20k miles. Once I put new Michelins' on it became a completely different experience with regard to noise, handling & comfort.

[RNajarian]

I’m leaning towards doing that. . . I’ll need to do research on the aspect ratio of the traditional tire. If it is not the same as the run-flat then the speedometer may need to be calibrated. Obviously I hope I can use the same rims.

[masraum]

Originally Posted by Icemaster

Driving a 2018 GLC300, OEM with run-flats that absolutely wrecked the comfort and ride.

Ebay. Found multiple stories on the MB forums where folks successfully added OEM toolkits and a comparable, temporary spare tire they sourced from a dismantler or OEM reseller for about a third that cost total.

I did the same, took about 15 minutes of searching.

Not your original question, but as soon as humanly possible - ditch those POS run-flats. Mine lasted 20k miles. Once I put new Michelins' on it became a completely different experience with regard to noise, handling & comfort.

That was my first thought. Find the last year that spares/tools came in them and figure out if they'll fit/work and find them at a junk yard (sorry, they identify as "dismantlers" now ).

I have planned to do the same with my boxster and even had a place that would have been a 2hr drive but was willing to sell the parts (spare and tools) for $125 or 150, but never jumped on it.

[RNajarian]

Forgive me if this is a dumb question. . .

The bolt pattern of the wheel is 5 x 122 mm. The current tire is 20”.

Would an Audi 18” 5 x 122 mm spare tire work on this car? At least to get it to a tire shop?

I know some calipers require spacers but aside from that . . .

[Tobra]

Are the bolts the same?


VW/Audi and Porsche used to use ball seats and many others used taper

[RNajarian]

Originally Posted by Tobra

Are the bolts the same?


VW/Audi and Porsche used to use ball seats and many others used taper

EXCELLENT POINT!

I don’t know but we’ll find out

[A930Rocket]

Originally Posted by RNajarian

Forgive me if this is a dumb question. . .

The bolt pattern of the wheel is 5 x 122 mm. The current tire is 20”.

Would an Audi 18” 5 x 122 mm spare tire work on this car? At least to get it to a tire shop?

I know some calipers require spacers but aside from that . . .

Depends on the back spacing as well.

Here’s what I use to check wheels and tire combos.
https://tiresize.com/wheel-offset-calculator/