is the tire feathering issue solely with the michelins from factory or is it something to do with a suspension component?? i ask because with my aftermarket wheels, do i need to worry about feathering still? Thanks guys.

 

Tire feathering is due to lack of tire rotation. Since you really cant rotate the tires (unless you dismount and remount them back on the wheels) they will wear a bit goofy. Shouldn't be any prob with the car at all, but instead something thats just going to happen with this setup

 

Really common with every car we service [Lexus and Infiniti independent shop] that has directional tires. Comes with the directional territory. Know situation for 15 years since directionals were created as rain tires to satisfy a marketing niche.
Brand new directionals have a little edge in performance that goes away when half worn [by 8,000 miles]......mostly something created to sell more new tires.

The appearance of performance. Note Michelin's newest top of the line tire [PS2] is non directional --------a bold move to go against the crowd

 

Q45 Tech, no flame intended as I lurk here often and respect your opinions.
I put over 120K miles on a Toyota MR2 that had Yokohama, and later Dunlop directional tires. Different sizes front & rear so I couldn't rotate them, or at least didn't feel like breaking them down and switching sides. I was careful to have it aligned each time I bought tires, which was often. I was lucky to get 12K on the rears, and about 24K on the fronts. They did however, wear very evenly with no signs of cupping and/or feathering.
That being said, I'm now going round-and-round with the dealer on my G35 Coupe. At about 8K miles I noticed that the tires were starting to sound like snow or truck tires, with a pronounced wopwopwopwopwop sound as I slowed down but in neutral and foot off the brake. I took it to the dealer, and the toe settings for both front wheels were out of spec. Everything else was fine. They aligned the car, but now I have F'd up tires. You can feel the cupping or feathering or whatever you want to call it if you run your hand around the tire tread. I feel that the alignment was out of spec right off of the showroom floor, and at minimum, I ought to get a new set of tires pro-rated for the 8K miles. The Service Mgr. is playing stupid with me and telling me that anything I read on the internet doesn't mean squat. We'll see.
If there was too much toe in or toe out, wouldn't the front end be kind of plowing or bulldozing, to use an exagerated example, when it goes down the road? Would this not cause the tire problems that many are reporting like noise, cupping, etc? Thanks.

 

I think the car comes with too much toe-in out of the box.

 

thanks for all the help guys. much appreciated.

is there anyway to check the toe-in???

 

The way to check toe-in, or caster or camber is to get an alignment.

I also had MUCHO TOE from the factory. Didn't know it until I started wearing out my stock Pilots around 10K miles. Didn't even bring it up to the dealer because the local boys pretty much suck around here. I did however pay for an alignment and my toe was so far out of spec that it blew my mind. (I'm talking a factor of 4 or 5 times out of the upper factory limit)

I guess you could say that I was pigeon toed.

 

I should have been more specific, as light performance cars with "low caster" don't seem to suffer as much heel/toe feathering IF alignment is spot on and the suspension is good as new [minimal suspension bushing wear].

The extreme amount of Caster used on heavy cars [with performance aspirations] combines with negative camber to create a tire block squirm in the presence of toe in. Going straight down the highway.

Think how the tire motion must be to create this effect as it rolls.

This phemonenon showed up on big MB/BMW in the very early 90's and any early Q45/LS400 that got fitted with directionals instead of the oem ultra soft fast wearing non directionals.

For year the tire suppliers and manufacturers blamed the effect was caused by too much toe in [static setting] yet going straight at 60 mph there is no toe in as the forward forces deflected the suspension bushings to a toe neutral position!

The problem was traced to an interaction [minor oscillation] betwen caster setting front tension rods and the tires......creating a fore-aft movement of contact patch as the tire rolled at certain speeds.........the tire block squirmed and was not hard enough and secured to the carcass with suffcient rigidity.........really a tire design problem that showed up on only certain cars on certain road types.

Reducing toe in sometimes works at certain speeds sometimes.

The are various degrees of heel/toe feathering-- hard to relate without feeling the exact amount vs mileage.......to make sure we are speaking of the exact same thing.

Unforunately alignment is ACTUAL misalignment [sitting still] in hopes of getting it RIGHT at forward speed. The designers measured rolling alignment at 55 mph and created a set of MISALIGNMENT specs that would optimize fuel mileage and minimize tire wear [minor benefit less critical weighting]

Accurate alignment requires you or your body weight be sitting in the drivers seat as the toe and camber will be different.........adding passengers or trunk weight will change things as will even an empty vs. full tank of gasoline. [I am being a perfectionist here]. Same with [excess or any] cambered roads [for drainage and to force cars away from center median].

Without rotation of direction the tires cannot be rewore in the opposite direction.

Why you have to check and adjust [mis] alignment every 90 days with expensive directional tires vs. every 6 months with non directionals. If you let the tire go more than 3-4,000 miles it is not reversable [the block damage causing the noise].

Why after fighting the situation for 7 years, I gave up and went back to non directional tires in 2000.........never looked back accepting the slightly lower performance.

Whenever I'm in the shop I feel a lot of tires [brands sizes] on Lexus and Infiniti looking for the magic tire that doesn' feather........no luck other than the Michelin Pilot H4 [a non directional tire or the top of other line non directionals].

Wish performance tire makers would shift back to non directionals and non staggered fitments but people want the nth degree for magazine comparisons.

 

Ahh, okay. doesnt the dealer give me one free alignment???

Q45Tech, good read thanks alot.

 

Or can you actually put non-directional tires on a coupe? My coupe is in the shop today for the same d**m thing: 8k miles and below 20mph it sounds like I'm running over potholes. I hate these Pilot tires...

 

Saw a new MB S500 with Pilot Sports at the gas station, the owner had tired 3 other brands of ultra performance directional tires in the last year........they all were MUCH more noisey than the Pilots after 8,000 miles.

Money seemed no object to him as he just tried tires to find the quietest. I sugested the Michelin PS2 non directional .........luckily 245/40/19 would fit on his wheels for the front.

The G35 lower weight [thus lower minimum load index] makes fitament a breeze compared to 4,000+ pound performance [type] cars.

 

Picked up my car from the dealer last night. Concerning the tire thumping they said the same thing- essentially this is what happens with directional tires/can't be rotated/live with it. I asked them if it was possible to put non-directional tires on the coupe and they said no. However, it is possible to put the same size tires front and back which would allow you to rotate them- at least driver front to driver back and passenger front to passenger back. According to them the only compromise might be a higher tendendy to plow in the front on tight corners, etc. But they also admit that they are not tire specialists. Guess I'll live with the thump for another 8k miles then go with something different. Also- how often is everyone getting an alignment done on their coupe?

 

DaBear - how much tire pressure do you use and how often do you check?
That thumping noise could also be coming from a flat spot.

You can use non-directional tires on the car if you can find the right sizes.
225/45/18, 245/45/18 on the 18" coupe wheels.

You may not want to use the same tire size front and back because it
will throw off your dynamic stability control. the rear needs to be a larger
diameter than the front.

I only get an alignment done when i notice a problem on either how the
car is handling or how the tire is wearing.

 

"only get an alignment done when i notice a problem on either how the
car is handling or how the tire is wearing."

TOO Late after the tires wear! Are you more sensitive than the alignment rack computer....."how the car is handling".

The cost of higher than average performance are significantly higher maintenance cost

To get a 10% improvement might double the maintenance cost per year compared to average cars.......brakes, tires, suspension.