Mixing Tires
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Joined: Jun 2011
Posts: 305
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From: Washington DC
2009 CLS63 AMG
Mixing Tires
i'm a huge fan of the michelin pilot super sports. unfortunetly my car came with continentals from the factory.
once i wear down the rears should i change all four or just the two rears. on my m3 when the rears went out i had put vents v12s with michellin PS2s in the front. on the freeway after 60MPH it felt like i was going to crash. the rears wanted to the grip the road a certain way but the fronts would fight. in other words the fronts were fast and the rears were slow. do you think i'll have this same problem with the amg?
option 1 - when the rears are shot replace all four.
option 2 - when the rears are shot stick with the continentals until the front are done then move to the pilot super sports.
..side note i have 5,400 miles on my car and the rears are still in great condition. what gives
so much torque and they're still awesome 
.. guess it's that LSD.
thanks.
once i wear down the rears should i change all four or just the two rears. on my m3 when the rears went out i had put vents v12s with michellin PS2s in the front. on the freeway after 60MPH it felt like i was going to crash. the rears wanted to the grip the road a certain way but the fronts would fight. in other words the fronts were fast and the rears were slow. do you think i'll have this same problem with the amg?
option 1 - when the rears are shot replace all four.
option 2 - when the rears are shot stick with the continentals until the front are done then move to the pilot super sports.
..side note i have 5,400 miles on my car and the rears are still in great condition. what gives
so much torque and they're still awesome .. guess it's that LSD. thanks.
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'09 SL Black, '12 ML63, '13 SL63, '14 E63 Wagon, '14 458 Italia
I'm personally a fan of not mixing tires, for the reason you describe. And the other point that always gets me is that this $100k car is only going to be as good as the 4 pieces of rubber that actually touch the ground, so why skimp there?
Thread Starter
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From: Washington DC
2009 CLS63 AMG
very true! but do you think i'll notice it as much in a CLS?
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From: Denver, CO
'09 SL Black, '12 ML63, '13 SL63, '14 E63 Wagon, '14 458 Italia
I can't think of a logical reason why a car couldn't be subject to the "wandering" phenomenon we've pointed out. And there's no real detriment to keeping the Conti's on until the fronts are close to gone (assuming you stay reasonable about it).
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2024 C8 Z06- 2025 BMW CS- 2022 Porsche 992 GTS
While its not taboo per se- its definitely not optimal to run different tread patterns on rear wheel drive cars. Now if its AWD you would be a fool to run different tires.
Your previous feelings about crashing when you change tires can be attributed to several things including but not limited to: road patterns, alignment, tire pressure, tread patterns (obviously) but also the tread depth of the front versus the rear. Often when one switches the rears only they create a new contact patch that is not matched up with the fronts. It happened to me on my M3 and my E63 and I kept the same brand of tire. I got that "floaty" feel because the tread in the rear was far different in depth than the front. As I drove the tires more and they broke in the feeling went away.
Your previous feelings about crashing when you change tires can be attributed to several things including but not limited to: road patterns, alignment, tire pressure, tread patterns (obviously) but also the tread depth of the front versus the rear. Often when one switches the rears only they create a new contact patch that is not matched up with the fronts. It happened to me on my M3 and my E63 and I kept the same brand of tire. I got that "floaty" feel because the tread in the rear was far different in depth than the front. As I drove the tires more and they broke in the feeling went away.
Thread Starter
Senior Member
Joined: Jun 2011
Posts: 305
Likes: 1
From: Washington DC
2009 CLS63 AMG
While its not taboo per se- its definitely not optimal to run different tread patterns on rear wheel drive cars. Now if its AWD you would be a fool to run different tires.
Your previous feelings about crashing when you change tires can be attributed to several things including but not limited to: road patterns, alignment, tire pressure, tread patterns (obviously) but also the tread depth of the front versus the rear. Often when one switches the rears only they create a new contact patch that is not matched up with the fronts. It happened to me on my M3 and my E63 and I kept the same brand of tire. I got that "floaty" feel because the tread in the rear was far different in depth than the front. As I drove the tires more and they broke in the feeling went away.
Your previous feelings about crashing when you change tires can be attributed to several things including but not limited to: road patterns, alignment, tire pressure, tread patterns (obviously) but also the tread depth of the front versus the rear. Often when one switches the rears only they create a new contact patch that is not matched up with the fronts. It happened to me on my M3 and my E63 and I kept the same brand of tire. I got that "floaty" feel because the tread in the rear was far different in depth than the front. As I drove the tires more and they broke in the feeling went away.
Last edited by Saeedg48; Feb 22, 2012 at 01:27 PM.
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From: THE Orange County, California
2024 C8 Z06- 2025 BMW CS- 2022 Porsche 992 GTS
I did confirm in my post above- the feeling went away after about 200 miles of good tire scrubbing/driving. The car drove like it did prior but those first few hundred miles sucked. I also had the toe set correctly and that was another factor because with the contact patch adjustment due to new tires the car needed some minor toe tweaks.
