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Discussion Starter · #1 ·
Note, car is bone stock. Is premium model AWD but has the 19" Sport wheels with Dunlop run flats (245/40/19)

I noticed some slight vibration (steering wheel, footwell, seat) at various speeds but more apparent around 80mph.

Reading these forums, there are a lot of reasons for this.

My first thought were the tires. Took it to Discount Tire for balance and they noted the fronts were at 5/32 and rears at 8/32.

They recommended balancing and swapping rears/fronts.

It did drive better but not al vibration is gone.

Question is can the variance in tread wear play a big factor in the vibration, especially since this is an AWD car.

I recall the rears generally power the car most of the time with the fronts coming on when needed.

Wondering if the vibration is coming on when power is being sent to all four wheels.

The vibration varies a bit but usually more under throttle vs coasting.
 

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Wondering if the vibration is coming on when power is being sent to all four wheels.
I hate to break it to you, but the AWD is essentially a 2WD with Infiniti using open diffs both front & rear.

As for the vibration, it could be a shifted belt in one of the tires causing the issue. Unfortunately, the spin balance process only goes to the equivalent of 50-60 mph, so the vibration you feel at 80 mph will be tough to replicate in the tire shop.
 

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Discussion Starter · #3 ·
I hate to break it to you, but the AWD is essentially a 2WD with Infiniti using open diffs both front & rear.

As for the vibration, it could be a shifted belt in one of the tires causing the issue. Unfortunately, the spin balance process only goes to the equivalent of 50-60 mph, so the vibration you feel at 80 mph will be tough to replicate in the tire shop.
Yeah I figured as such. I really didn't think it was due to varying tread wear.

I plan to replace these tires but not quite yet.
 

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If they are the stock OEM Dunlops I would be looking at them as an issue and simply riding rough due to wear, if they aren't
the stock tires then it could be a worn outer-tie Rod or a large pothole messed up your suspension alignment.

I'm going through the same process on my G37 at the moment, hopefully just wheel balance I didn't plan to replace
my suspension until the summer. XD
 

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Note, car is bone stock. Is premium model AWD but has the 19" Sport wheels with Dunlop run flats (245/40/19)

I noticed some slight vibration (steering wheel, footwell, seat) at various speeds but more apparent around 80mph.

Reading these forums, there are a lot of reasons for this.

My first thought were the tires. Took it to Discount Tire for balance and they noted the fronts were at 5/32 and rears at 8/32.

They recommended balancing and swapping rears/fronts.

It did drive better but not al vibration is gone.

Question is can the variance in tread wear play a big factor in the vibration, especially since this is an AWD car.

I recall the rears generally power the car most of the time with the fronts coming on when needed.

Wondering if the vibration is coming on when power is being sent to all four wheels.

The vibration varies a bit but usually more under throttle vs coasting.
The tire that is at 5/32 is awfully close to 1/8 inch which is where the tire should be replaced. My experience is that marginal quality tires that are near EOL will give trouble. Belts shift, etc.
You should consider replacing those tires. Those Dunlop run flats were crap to start with. Search the forum. You will find very little good to say about them.
 

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Discussion Starter · #6 ·
The tire that is at 5/32 is awfully close to 1/8 inch which is where the tire should be replaced. My experience is that marginal quality tires that are near EOL will give trouble. Belts shift, etc.
You should consider replacing those tires. Those Dunlop run flats were crap to start with. Search the forum. You will find very little good to say about them.
Yeah, it looks like original owner had replaced two of the tires.
 

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The tire that is at 5/32 is awfully close to 1/8 inch which is where the tire should be replaced. My experience is that marginal quality tires that are near EOL will give trouble. Belts shift, etc.
You should consider replacing those tires. Those Dunlop run flats were crap to start with. Search the forum. You will find very little good to say about them.
Agreed. It wouldn't surprise me at all if putting new tires on your car resolves your problem. The number of recalls Dunlop has issued for defective tires is troubling to say the least. Don't cheap out and only replace two tires either. Your AWD doesn't like tires of different diameters and replacing the 5/32" tires with new ones will put even more strain on the AWD transfer case due to the difference in tire diameters. An 1/8" of an inch difference in tire diameters doesn't seem like much but it is to the AWD system.

The difference between the front and rear tire tread depths makes me think the tires weren't rotated frequently enough to maintain equal tire diameters. Tire rotations should be done every 5K miles to maximize the lifetime of the tires.
 

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Discussion Starter · #8 ·
Agreed. It wouldn't surprise me at all if putting new tires on your car resolves your problem. The number of recalls Dunlop has issued for defective tires is troubling to say the least. Don't cheap out and only replace two tires either. Your AWD doesn't like tires of different diameters and replacing the 5/32" tires with new ones will put even more strain on the AWD transfer case due to the difference in tire diameters. An 1/8" of an inch difference in tire diameters doesn't seem like much but it is to the AWD system.

The difference between the front and rear tire tread depths makes me think the tires weren't rotated frequently enough to maintain equal tire diameters. Tire rotations should be done every 5K miles to maximize the lifetime of the tires.
I would be happy if the only issue were tires.

I'll see about getting CarMax to replace the tires. Otherwise I'll get some Continental DWS06
 

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I would be happy if the only issue were tires.

I'll see about getting CarMax to replace the tires. Otherwise I'll get some Continental DWS06
Good luck! Hopefully, that's all it is.
 
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