After experiencing my first snow shower a few days ago, I've started thinking about getting some winter tyres for my SLK to get me through the cold winter months in the Scottish Highlands.
I currently have the 18" AMG alloys that came with the AMG package, with the sport package suspension. I can only find one winter tyre that matches the standard size for the rears and they are Ł400 each! I did think about getting a slightly different tyre size, but then I started thinking about just getting a set of winter wheels.
I've found locally a set of genuine Mercedes 17" alloys from a B Class A246 (wheel part no A2464010502). They are fitted with winter tyres and seems like a pretty good deal, but I'm not sure if they will fit. I've done a bit of searching and reading up but my head is starting to spin so I'm hoping someone more knowledgeable might be able to advise! I've used the online calculators to determine that the rolling radius will be less than 1% different so there's no problem there. It's the wheel width and specifically the offset that I'm not so sure about.
My current setup:
Front: (225/40/R18) 7.5J ET 37
Rear: (240/35/R18) 8.5J ET 30
Proposed winter wheels: (225/45/R17) 7.5J ET 52.5
Online comparison results (click links for full results and illustrations)
: "Compared to your existing wheel, this new wheel will have an inner rim which is 15mm closer to the suspension strut. The outer rim will poke out 15mm less than before."
: "Compared to your existing wheel, this new wheel will have an inner rim which is 9.3mm closer to the suspension strut. The outer rim will poke out 34.7mm less than before."
The fronts don't seem too bad to me being 15mm recessed at each side, but the brake calipers are very close to the wheels already (I'd say about 14mm clearance) so I guess I would need spacers.
The rears seem a lot worse but I suppose that's to be expected with a skinnier wheel. There is already about 40mm of clearance for the brake caliper so that wouldn't be an issue, apart from maybe looking silly with the wheels recessed so much. Would the wheel be likely to foul the suspension being 9.3mm closer than standard? If I were to use spacers here, what is the biggest spacer I could use without having to make any other changes?
Thanks in advance for any advice on this!