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Discussion Starter · #1 ·
Did not think I would be having this discussion so soon, however, I need some feedback on the longevity of our tires. As some would know, I got a set of 235/35/19 Michelin Pilot Sport 4 S put on in December 2017. I have had them rotated, balanced and aligned every 6 months, last one just yesterday, in order to avoid the issues I had with the original Pirelli P-Zero's that only lasted 11,000 kms (just under 7,000 miles), the front ones in particular were very badly grooved on the inside track. I was told at the rotation yesterday that my tires were on the way out and I would probably only get another month or two out of them, they have done 37,000 kms (about 23,000 miles) in the two years. The thing that irritates me is (perhaps mistakenly) I expected a lot more longevity out of them, and the inside track groove is starting to show again, just like the Pirelli's. Is this mileage the best I can hope for? I know there are many variables, not least tire pressure, road condition, how hard you push the car etc etc., I just thought these Michelin tires might give me 45 to 50,000 kms (30,000 miles) at least.
 

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Hey you remember those ludicrous tire wear charts? Anyway .......
The 23k is not so much the issue ... I think the 4S compounds are made to roll straight well and grip well on corners so The inner treadwear vexes the mind ... took a look at the camber angles over the suspension travel and they seem nominal. And even though both front and rear camber is negative I did not see inner tread wear
The dynamic toe out if too much will eat the inner tread blocks ... if the static toe is good then the bushings have gone sloppy
Maybe for your particular case the toe needs to be at the toe in end of the spec??
 

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Discussion Starter · #3 ·
Hey you remember those ludicrous tire wear charts? Anyway .......
The 23k is not so much the issue ... I think the 4S compounds are made to roll straight well and grip well on corners so The inner treadwear vexes the mind ... took a look at the camber angles over the suspension travel and they seem nominal. And even though both front and rear camber is negative I did not see inner tread wear
The dynamic toe out if too much will eat the inner tread blocks ... if the static toe is good then the bushings have gone sloppy
Maybe for your particular case the toe needs to be at the toe in end of the spec??
Thanks jmc!
I'm just looking at the tire data from the rotation yesterday, for the front axle it has the 'before' toe left 1.6mm and toe right 2.0mm. Target data should be 2.1mm with a variance +/- 1.1mm. After alignment left toe 1.1mm right toe 1.1mm.
As for the front axle Camber, left -1'50 right -2'02 cross 0'12 Target data should be left and right -1'48 with a variance +/- 0'20 cross should be 0'00 with variance +/- 0'24. After alignment left -1'45 right -2'04 cross 0'19

I have to admit I don't quite understand the figures enough to pick if the toe settings and/or camber are in some way effecting the inner track wear.
 

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That toe data ... in or out from naught??

The camber will flex somewhat over time what with shock tower metal changes driver mass road impact etc but those are about right
 

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oh duh nevermind ... +1.1mm is toe in ... that's ~0.1deg inward for a 235/35-19 setup (assuming the suspension components hold without give)
either way your toe was in so now not sure why the inner tread blocks over wear pattern?
if you jack the front up and reeeeeeeealy yank the wheel along the axis of the car do you feel any give? other than the car almost falling off the jack stands?
is your steering rack system tight? like if you push hard on the steering rods towards the car centerline do they give at all?
i hate perplexing situations! i'm getting too old for this :p
 

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Discussion Starter · #6 ·
oh duh nevermind ... +1.1mm is toe in ... that's ~0.1deg inward for a 235/35-19 setup (assuming the suspension components hold without give)
either way your toe was in so now not sure why the inner tread blocks over wear pattern?
if you jack the front up and reeeeeeeealy yank the wheel along the axis of the car do you feel any give? other than the car almost falling off the jack stands?
is your steering rack system tight? like if you push hard on the steering rods towards the car centerline do they give at all?
i hate perplexing situations! i'm getting too old for this :p
Sorry to cause you sleepless night jmc ;) I will get the car up on my brother's hoist as soon as possible and do the appropriate manipulations as you suggest, it concerns me as well that I have seen two sets of front tires bald and groove on that inner track even with my regimented rotate, balance and align process. I have a service due in December, I may ask the stealership to take a good look at the rack and rods and see if there is any 'clear and present danger'. As always, thank you for your considered wisdom.
 

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No worries ... i love puzzles, frustrating or not
The castor and camber are not really adjustable unless you fit aftermarket strut top plates etc and the tiny changes stemmed from the toe adjustments since the mechanical linkages creates the dependencies ... so it comes down to suspension components stability, like the bushings tie rods steering rack bla bla bla
Something is either causing excessive toe out during suspension travel, or the setup geometry is wrong from the factory or it got messed up post delivery
Feel the front tire surfaces and compare them to the rears ... if the fronts are suede like and the rears are like 1500grit sandpaper then that tells a story
May the force be with your new tires! Good grief
 

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Discussion Starter · #8 ·
I have decided to try yet another brand, I have ordered the Continental SportContact 6 to replace my Michelin Pilot Sport 4 S, let's see what happens... the tire dealer 'promises' me better longevity and a quieter ride on the new Conti's. I know the branding is different in the US, @jmc are the SC 6 similar to the ones you have just put on?
 

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hi all
new guy here, i just got a cpo 16 sport plus.
the dealer had put on mich pilot sport as3+
i took the psi to 31 cold. i find them pretty comfortable.
i'm in ny so need the a/s. of course cant speak for longevity.
cheers john.
 

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I know the branding is different in the US, @jmc are the SC 6 similar to the ones you have just put on?
Seems the SC6 is somewhat different from the ECS ... and now you’ve done it gave me more stuff to read you so and so
They put the SC6 on the Audi R8 V10 so must be better than the average rolling carcass ...
 

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i was gunna say 31 might be a bit low. I run 37 all around
 

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Discussion Starter · #14 ·
Seems the SC6 is somewhat different from the ECS ... and now you’ve done it gave me more stuff to read you so and so
They put the SC6 on the Audi R8 V10 so must be better than the average rolling carcass ...
I hope that they are, however after digging a little deeper (after I pulled the trigger) I discovered the wear rating on the Michelin PS 4 S is 300, where on the Conti SportContact 6 it is 240. Now the problem here is, the main reason I went to Continentals was the perception of greater wear on my Michelins. However, I still believe it is not the tires as such, I think the main issue is still in the front end of the vehicle, tires don't develop inner track grooving in normal commute driving. I am sorry to drag you into my insanity JMC, but as they say, a problem shared is a problem solved! :cool:
 

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... However, I still believe it is not the tires as such, I think the main issue is still in the front end of the vehicle, tires don't develop inner track grooving in normal commute driving...
Your 2019 rather unique experience drops here without a solution.
One commentor seen elsewhere, felt the camber factory setting was the cause, in favor of better handling characteristics.
Road conditions? Any issue with your other vehicles?
 

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Discussion Starter · #19 ·
Your 2019 rather unique experience drops here without a solution.
One commentor seen elsewhere, felt the camber factory setting was the cause, in favor of better handling characteristics.
Road conditions? Any issue with your other vehicles?
Hi Geo, I think its a lot more to do with how I drive the car and the road conditions where I am. As I have just posted in the other thread, the camber setting is all part of the more aggressive handling of these vehicles, so altering it (and things like toe settings) will ultimately have a negative effect on how the car handles. The SA basically told me to suck it up, rotate the tyres more often (as the rear tyres are still pristine) and just accept that I will have to shell out for new rubber more often, or alternatively, change the way I drive the car.
 
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