edgar86

Hi there ,
I just noticed my spare wheel is 17" and all my 4 wheel are 19" ,
should i keep it or is it useless and will harm the 4 Matic transmission ?

Rascally Wabbit

Overall rolling diameter of the 17" spare will approximate the diameter of the 19" or 20" OEM wheel due to the different aspect ratio when inflated. MB offers a 17" winter tyre package in certain countries which again have the roughly the same diameter. You can play with these dimensions on www.tirerack.com There is no need for concern.

edgar86

Hmm if i understand ; you say this wheel goes to same diameter as the 19" when inflated ?

Rascally Wabbit

This video shows how they inflate. With supplied pump, it will take longer but it will work, about 5 minutes.

edgar86

ah ok i never saw something like that , going from my French Renault car to the MB world is amazing
thanks for showing me the light .

sblvro

Thanks for this pic! Didn't know it came supplied with its own pump!

Bob338

Unfortunately I had occasion to have to drive several hundred miles on my spare which was mounted on the right front. Because of the disparity I questioned what effect it might have on steering. I've used different size tires on the front on non 4 wheel drive vehicles. The difference in size is immediately noticeable.

In this case I noticed absolutely no difference in steering or driveability. Only problem was having to drive under 50 mph. They've obviously figured it out as to size, which is probably the reason that spare is so damned expensive.

rmfnla

Going from anything French to anything else is probably amazing!

I've owned a few French cars; it's like they are from another planet...