R350 Ride Quality Question
Thread Starter
Member
Joined: Jun 2014
Posts: 179
Likes: 20
From: Southeast Florida
06 SLK55 AMG, 12 R350
R350 Ride Quality Question
I have a 2012 R350 with the rear air suspension and have been running on a 9/32 set of all season 255/50r19's (Conti Cross Contacts). This is the factory tire size running on the standard equipment OE rims. At 38-40 psi, the ride is awesome and smooth even on poor roads. It feels like riding in a limousine.
The other day I swapped on a set of 20" AMG rims from a 2011 r350. They had a set of 6/32 set of Pirelli Scorpion Zero summer tires (265/45r20) also running at 38-40 psi.
My problem is the ride quality (something very important to me on my R) right after the swap has deteriorated noticeably. I feel so much more of the road now and am pretty disappointed. My wife says the change is like going from a comfortable sneaker to hot stiletto shoe. they look hot, but they aren't near anywhere as comfortable.
Comparing the two tire sized on tiresize.com the 255/50r19's are 29" diameter, 5" sidewall, and 10" wide.
The 265/45r20's are 29.4" diameter, 4.7" sidewall, and 10.4" wide
So my question for you guys is this. Should loosing 3/10's of an inch in sidewall height make that much difference in ride quality? Is part of this problem caused by changing the brand and season rating? Short of going back to the 19" setup, can you suggest any iseas to improve the ride quality, maybe trying to find a taller 20" tire size?
While I can, I really don't want to go back to the 19" rims. Any ideas would sure be helpful. Thanks in advance.
The other day I swapped on a set of 20" AMG rims from a 2011 r350. They had a set of 6/32 set of Pirelli Scorpion Zero summer tires (265/45r20) also running at 38-40 psi.
My problem is the ride quality (something very important to me on my R) right after the swap has deteriorated noticeably. I feel so much more of the road now and am pretty disappointed. My wife says the change is like going from a comfortable sneaker to hot stiletto shoe. they look hot, but they aren't near anywhere as comfortable.
Comparing the two tire sized on tiresize.com the 255/50r19's are 29" diameter, 5" sidewall, and 10" wide.
The 265/45r20's are 29.4" diameter, 4.7" sidewall, and 10.4" wide
So my question for you guys is this. Should loosing 3/10's of an inch in sidewall height make that much difference in ride quality? Is part of this problem caused by changing the brand and season rating? Short of going back to the 19" setup, can you suggest any iseas to improve the ride quality, maybe trying to find a taller 20" tire size?
While I can, I really don't want to go back to the 19" rims. Any ideas would sure be helpful. Thanks in advance.
Member
Joined: Mar 2016
Posts: 86
Likes: 10
From: Vancouver, BC
2013 R350
there is 2 factor to this. The rim size and the different tire brand and model. I would believe the 1" different shouldn't make a huge difference. I have 20" winter and 22" all season for the summer months. they both ride comfortably. Summer tire tends to have stiffer side wall for better corner performance. Also something to consider is the age of the tires. if the summer tires is old and have seen winter it can cause the tire compound to harden.
Thread Starter
Member
Joined: Jun 2014
Posts: 179
Likes: 20
From: Southeast Florida
06 SLK55 AMG, 12 R350
Interesting info. Thanks for the input
It would be pretty safe to say the 20" tires are older than the 19's. How much older I couldn't say. But that summer tires have a stiffer side wall than all-season, that I didn't know.
I also read in another thread:
The other thing I was looking at is the Consumer reports tire ratings. One of the things they measure is ride quality by brand, so using that as a reference might help the situation as well.
One thing for sure. I'd really like the 20" wheels to stay. I was thinking to go with a replacement tire having a taller sidewall (say a 265/50r20 that has a 5.2" sidewall). It's not a lot, just another .5 in sidewall height over the stock 20" tire.
But considering how much difference between the difference between the 255/50r19 sidewall of 5", and the 265/45r20 sidewall at 4.7, clearly the R is sensitive to these small changes.
Only thing is I'd have to remember that when my speedo is reading 75mph, I'm really going 78. Any thoughts on that?
It would be pretty safe to say the 20" tires are older than the 19's. How much older I couldn't say. But that summer tires have a stiffer side wall than all-season, that I didn't know.
I also read in another thread:
If you install BIG wheels, the airmatic suspension will compensate for ride harshness after a few trips. I went from 18" to 22", it was terrible the first day and perfect the second. The wheels weight much more which is bigger influence then the smaller sidewall. It now rides like a true Mercedes without having to use sport mode.
One thing for sure. I'd really like the 20" wheels to stay. I was thinking to go with a replacement tire having a taller sidewall (say a 265/50r20 that has a 5.2" sidewall). It's not a lot, just another .5 in sidewall height over the stock 20" tire.
But considering how much difference between the difference between the 255/50r19 sidewall of 5", and the 265/45r20 sidewall at 4.7, clearly the R is sensitive to these small changes.
Only thing is I'd have to remember that when my speedo is reading 75mph, I'm really going 78. Any thoughts on that?
