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After driving a 2010 S550 for 6 years, it was time to trade her in for, of course, another S550 (2016 model purchased a year ago). The run-flats and no spare caught me off guard but there are many posts on that issue/debate. For me, I am tired of replacing rear tires with each oil change and front tires with every other oil change - a slight exaggeration but only slight. I’m getting about 10-12k miles on the rear and 20k on the front (Michelin Pilot Sport A/S 3). I am driving 30k miles/year. The “chat guy” on tire rack suggested getting 18” wheels that are not staggered and then I can get some 70-80k mile tires (with full rotation). Does anyone have experience moving from 20” AMG wheels to a 18” wheel? I would imagine the ride comfort may improve (if that is possible) but the handling will suffer. Will 18” even fit? I’m concerned about lug nut alignment and offset for brake calipers. My goal here is to figure out a way to get 50k+ miles out of my tires - please don’t recommend getting a Honda... Any suggestions would help. Thanks!
i solved my tire wear issue by getting 4 20 inch non staggered wheels, find 2 rears or 2 fronts and change them out so all 4 are the same, it will still look great and you wont have to replace tires as often.
As cars gets stiffer and stiffer body shells and more and more electronics are helping control the mass wobbling about, it has enabled the marketing team to throw bigger wheels to look more blingy. Early on they never bothered to tune dampers, suspension bushes and set up to cope adequately. But on a this sort of car and being this late, I would expect it to cope with 20" but would ride better with 19"
Dropping to 18" is a big change. You could well find you need to programme various modules with the change in tyres. ESP, ABS, Traction, Cruise, Sat Nav would all want to know if each wheel's circumference has changed. On this even magic carpet ride might need to know. It should all be fairly simple for a competent dealer (if there is such a thing!), as winter tyres should have similar issues, and they cater for that.
Of course Run flats are shocking trash that ruin ride and handling. Going to stock real tyres would be a huge benefit, but I'd test the car for a week with that size before committing to the expense as you may not like how the car behaves (and you need to find a solution that suits for punctures).
A few other key ideas
1) Are you sure the tyre wear isn't predominately a 2.3 tonne tank with a rocket engine being deployed? Turbos have led us to drive in a very lazy planet destroying manner. Many unnecessarily end up using 300lbs ft of toque to move 10 yards in traffic. Turbo's have made many addicted to the rush easy acceleration (we don't need) gives.
2) 20", run flats and terrible roads will knock the geometry out far more frequently than cars with 18" real tyres and good roads.. Trying to find a competent garage that can point all 4 wheel in the right direction is almost impossible. Especially when various bolts they don't have are required to set it up properly after the factory never bothered.
3) Tyre pressures? modern cars run silly tyre pressures. Germans have perfect roads and do 120mph all day long, so 36 PSI is probably underinflated. If you wanted some form of ride comfort I expect you have yours at 26 PSI?
those three points will knock tyres out quick. As another thought. UK motoring mag struggling to get 8k miles out of the FRONTS ! on a new 8 series thing
I appreciate the replies. I didn’t think about how going from 20 to 18 could effect the various modules. I’m about a month out from doing something and now I’m leaning towards staying with 20s but not staggered, if I can put 70k rated mile tires on the 20s. Thanks again and safe travels!
I have S65 W221 with mixed front / rear 20s
Specs from my manual included
Very important to me to keep road noise down and have great grip. We live in a tropical environment so it certainly can break out aquaplaning when your tires get down.
I have enjoyed the FALKEN FK510 275/35ZR20 (102Y) for the rears and 255/35ZR20 (97Y) showing very little wear and the new generation is sticky enough. They are also very economical not that it concerns me that much.
Regards,
Grant
New rims ordered as standard rims were not fitted as per option 4 below. and were not genuine i.e. not AMG
Ordered some that suit the 2016 model genuine AMG 20inch light alloy which as you can see from page 720 in 2008 is acceptable
769 were forged.
There is advice you might need re offsets but this was the final I ended up with..... IF CHANGING RIMS MAKE SURE YOU DONT GET HAD WITH FAKES THEY ARE EVERYWHERE CHECK FOR MARKINGS
Dropping to 18" is a big change. You could well find you need to programme various modules with the change in tyres. ESP, ABS, Traction, Cruise, Sat Nav would all want to know if each wheel's circumference has changed. On this even magic carpet ride might need to know. It should all be fairly simple for a competent dealer (if there is such a thing!), as winter tyres should have similar issues, and they cater for that.
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Nah, I do this every winter when I take off my 20 summer tires and fit 18 winter tires. This with no problems whatsoever.
If what you state was actually required, it would be so stated in owners manual.
I appreciate the replies. I didnt think about how going from 20 to 18 could effect the various modules. Im about a month out from doing something and now Im leaning towards staying with 20s but not staggered, if I can put 70k rated mile tires on the 20s. Thanks again and safe travels!
Keep the 18" tire diameter close to the 20" tire diameter specs and you're fine. The size of the actual wheel does not matter as long as it clears the calipers, it's the tire.
12-30-2019, 11:36 PM
