Chromatic

iTrader: (4)

Hey guys,..

I'm now a new owner of a 2008 350Z! With 26k miles.. super clean.

Had one issue though on the test drive.

At LOW speeds,.. we are talking 10-15mph and lower.. A noise comes from what sounds like the driver front wheel area.

It sounds like you put an H rate piece of crap tire on the front driver side tire and it picked up ALL the road noise. Or, maybe like you had really low brake pads and the noise when you apply them.. no screeching but more of a road noise "roar" .

IE: I'm coming to a stop,.. About 10-15mph the noise starts and remains till I'm stopped completely. Yes, I released the brakes to make darn sure it wasn't them.. (Brake job just done 3 weeks ago by Nissan).

More clues:

After 15mph or so.. the noise goes away.. 55mph fine.. 75mph fine.. perfect.

Only other thing I noticed that may tie into it.. is at about 85+ MPH it starts a stutter sound.. I can recognize the feel and sound instantly in any car.. this is definitely a wheel balance issue at the high speed. It's not major, most normal people wouldn't even do anything about the balance of the high speed, but I do.. and I know balanced wheels help the tires wear a little better, etc.

Any ideas of what could be going on? Remember, it's a pristine, 2008 350Z,.. with 26k miles -- Has all work (including oil changes and reg. maintenance) done AT Nissan.. never been taken anywhere else by the owner I bought it from. (He proved it to me with a stack of papers a mile high from nissan .. getting charged for a lot of "unecessary" checks, and "Maintenance".. But that's part of the reason I bought it from him, because the carfax also shows everyone of those Nissan appointments..

I just need ideas from you guys on what all possible scenarios this could be. The guy and I signed a legal document that we had notarized saying he would pay for ANY mechanical issue with the car to NISSAN particularly. He didn't say go take it to some cheap mechanic, he said, I want you to take this to Nissan,.. I've taken super good care of this, had all work done at Nissan, I listed it as in perfect Mechanical condition -- so if Nissan finds an issue with it.. I'll pay. (That's when we wrote up the legal document, and we both signed, dated, and then had it Notarized with 5 witnesses (just cause we had that many people in the room at the time) ).

So whatever it is , it's getting fixed.. I'll bring it to Nissan Monday coming up.

In the mean time I just want to try and get an idea of the possibilities it may be.. to help explain it to them, and maybe put some ideas in the mechanics head(s) of what to be checking for.

Is it even remotely possible that the wheel(s) could be off balance that bad and make the louder noise at very slow speed, and a little stutter at 85+ mph? But the car drive perfect between 15-80mph ?

I didn't know what category to put this in.. as to me it could be Tires, Wheels, balance,.. or suspension based. So I apologize about the "general" category.

Thanks for your ideas/advice,

Waiz

iTrader: (57)

Most likely you either have a bent wheel, improperly balanced wheel, bad tire, or a bad alignment

winchman

That's definitely an indication of tire feathering, which I mentioned in my post on your other thread.

You might be able to save the tire if you can find someone to true just the inside edge, but not many shops have the equipment or skills needed to do that any more. You'll probably need to replace both front tires. Then have the alignment done at Nissan to be sure they follow the TSB when setting the toe-in. I'd try to get the dealer where you got the car to cover the expense.

I caught mine before the tires were ruined, trued them myself, and fixed the toe-in. I've put about 4K miles on it since with no further problems.

Chromatic

iTrader: (4)

sounds like this is the problem..

It's an 08.. the TSR I saw online said the 2003 models.. I guess they never fixed it?

** You said get the dealer where I got the car to cover the expense.. I bought private party. It's an '08. Anyway Nissan covers this cause it's their design fault ?

Anyhow.. these tires have tread on them.. but they aren't brand new .. not sure if they are factory with 26k miles on them, OR if they've been replaced once.

Either way -- the guy said he'd pay for any mechanical issue beyond $200.. but this is a little gray area.

I need to know exactly how to handle this really. How can I tell if the tires are salvagable?

Visual inspection enough? And if so.. is it just if there isn't obvious flat spots on the inside of the tires up front they don't have to be replaced?

If they have to be replaced.. what do you recommend tire wise, best money wise and still "good" tires for the Z?

Can I do just the two front with new tires and leave the back if short on funds?

And.. this seems pretty darn specific -- I'll get Nissan to do it regardless.. but it sounds like I'm going to need to bring something for them to look at to do this *right*.. what would you do if you weren't adjusting it yourself.. and needed to get it fixed as cheap as possible, but by Nissan.. but of course wanted them to get the adjustment exactly right?

And.. would this qualify as something this guy should pay for? Technically, he should have noticed the roar as a problem.. and while he had it UNDER warranty had it fixed..

Am I looking at possibly 100-200$ here? If I need tires.. what kind of money + fixing the adjustment getting Nissan to do it am I "ballpark" looking at. I may go half and half with the guy considering the issue.. but I really don't have a grand to sink into this car after I Just put 17.5k into it.

Your help is really appreciated,..

Chromatic

iTrader: (4)

Also -- looking though the MONSTER thread on feathering:

https://my350z.com/forum/maintenance...g-fyi-204.html

205 pages+ -- I obviously didn't read even close to all of it..

But,.. people are talking about bushing replacement in there.

I want to fix this.. but get it fixed right. Is this something I need to grab some aftermarket bushings and bring with me to the Nissan dealership and have them pull up the TSB -- align (and rotate possibly) the front tires.. AND put the aftermarket bushings in while they are at it?

Nissan will throw in aftermarket bushings if you accept an "as-is" no warranty on the work right?

Or should I just go to Nissan and have them pull the TSB , switch front left with front right tire.. and re-align the wheels to proper toe/camber etc.. according to TSB specs which sound like right around 0.0 (-.1, +.1) or so is about right?

I visually inspected the tires (didn't spin them, didn't jack it up).. and the tread is worn more on the very inside oh, half inch to inch of the tire closest to engine.. but it's not visually obvious really.. But when I measure the tread left on the outer tire and the tread left on the inner there is a definite 1-2mm difference.

So perhaps, just maybe,.. I don't have to grab new front tires?

And again, now I'm a little confused with that thread I posted.. cause it sounds like they are saying you need to replace bushings with stronger aftermarket ones due to how much movement the factory ones allow -- and if you don't my "roaring" sound and uneven wear of tires will just come back?

Thoughts? -- I'm going Monday to Nissan to get this sorted, but I like to have exactly what I want done specifically in my mind. I'm not the type to just hand it over and say it's making a noise,.. fix it. Unless I have no resource like you experts to point me in the right direction.

Thank you,

winchman

It takes surprisingly small flat spots to cause the noise. The way I could tell they were there on mine was to put a ruler on the area, and rock it back and forth around the tire. (The pic shows the ruler on the outside, but it's just to give you the idea about how to place it.) You'll be able to feel the straight edge bump as it coincides with the flat spots.

I only had to remove about 1/64" (probably less) of rubber on the innermost rib of both tires to get rid of the flat spots and the noise. I couldn't find anyone around here with a truing machine, so I did it myself with a router and carbide bit on a homemade truing jig.

The combination of very soft tires and the unique suspension design on the 350Z makes setting the toe-in critical. You cannot have any hint of toe-out.

Installing stiffer bushings should help, but that reduces the supposed benefits of the design. Some of the early press releases talk about the design reducing bump-steer or something like that. They went back to a conventional design with a single lower ball joint on the 370Z, though.

Replacing the tires with ones that have a harder compound should help keep the problem from coming back, but you probably don't want soft tires in the back and harder ones in front. I'll definitely go with a harder tire when the time comes to replace them.

I don't know what kind of tires you have, but you may be able to reverse them on the rims, inside to outside, and that would probably solve the noise problem until it's time to replace them all with something harder.

This isn't an end-of-the-world issue. Let's see some pics of your new ride.

Chromatic

iTrader: (4)

Thanks winchman.. I was honestly expecting to be able to turn the wheel, or get up under the car and shine a flashlight at the inner edge and see a balding flat ring around the inner portion of the tire .. but that isn't the case ... Seems feathering is it skipping on the inner part of the tire.. wearing one spot a little, not the next X inch(s).., then the next spot and so on.

The inner and outer part of these tires look the same.. but I don't know how many tires you can flip on a single rim/wheel. I believe these a Michelins,.. I'll go have a look soon to see what exact make model.. and snap a picture of them or two if it'l help any.

I was looking at tires online for a "worst case scenario".. and I don't know .. I see some good deals at the 225/45 R18's -- Like.. $500 for a set of 4.. but, brands I just don't know.

I know Michelin is generally good, and expensive. And I remember putting some "Falken" Tires on my 1991 300ZX that were just fine replacements, not noisy to me.. worked fine. I do remember the V, and Z rates.. essentially speed ratings and all that.

I guess I need to try and figure out what "brands/types" of tires are not crap but that I can get without paying a grand for tires if I should go that route.

And this issue makes sense in my head -- Because at high speeds the suspension spreads out to the outside of the wheels.. I think of it as the wheels sort of spreading out (in my mind).. but at low speeds they sort of clench in on themselves.. and angle a bit (toe out?) like coming to a stop.. at this angle the tires then are putting the most pressure on this inside bit of the tire that is now worn unevenly and it makes one heck of a noise which explains the issue in my mind.

I have to admit toe in, toe out.. camber this, camber that I'm not an expert with.. but I do get it, I've just never done any suspension work myself. Once I do any project myself in my own garage I never forget it.. but suspension work hasn't been one of them.

Sounds like I need to look at tires over the weekend (when I figure out what brands are good enough, but decently priced).. then hit up Nissan Monday with the issue of the Noise. Tell them there is a TSB (I suppose having the TSB number would make it easier?).. and I need to essentially get an alignment.

But, as you say.. if the tires can't be flipped on their own rims.. an alignment isn't going to correct the worn tires? Almost sounds like new tires are the only way to go here, .. cause if it's making the noise the tires have to be feathered right? Just a proper alignment won't resolve the issue.

Thanks for your help!

Chromatic

iTrader: (4)

Just an update on tires on the car..

The car has GoodYear Eagle F1 - All Season 225/45 R18's -- And they are *directional*. So it's not going to be an option to rotate them on the front wheels.. Sounds like at minimum a new set of front tires will be needed.

Would it be wisest to just go for a new set of tires all the way around for better ride quality and obvious even wear, etc?

I've been looking at Tirerack as advised from the search on this forum.. and found some sets of tires from mid 400's.. to $800. If I could get away with around $500 for a set I'd be pleased. Then we'd have mounting, balance, valve stems, disposal fee's.. and would still need the Nissan alignment.

Would you get the tires put on at XYZ approved tirerack place (where I could have them sent to).. THEN take the car with new tires to Nissan for an alignment? Or would you bring the new tires to Nissan and have them do it all?