A tire question from an Infiniti Tech

[SteveTheTech]

Hey y'all, This question goes out to all the G coupe drivers with stock or stockish tires and suspension. I know that road noise is very evident when decelerating or braking, especially with the stock Michelin Pilot Sports that 03-04 w/ 18" wheels, the Potenza's used on the 05-06 sport coupes w/ 19" are slightly better. My question is what if anything have you done to correct this issue, what type of tires have you found that work to resolve the noise ? I would assume that a camber kit and a new set of rubber would solve it once and for all but I am really curious to hear if anyone has found the magic tire for this.I know the reason for the noise is suspension geometry and a lack or research on long term testing of the tires. I see many people with this issue and it drives me nuts I would like to recommend something to my customers that will wear evenly and not feather edge on the inside shoulder causing the noise. I have seen several attempts that have not worked so well so any feedback on this would be greatly appreciated by me and I am sure there may be someone left on this forum with stock tires that is tired of talking over the roar of the front tiresThanks

[RED_DET]

The directional tires seem to be an issue and some have gone to asymmetric tires so they can be rotated side to side to knock down the feathering. You can also reverse mount the the directional tires every 5-6k miles. Not really much else except what you already mentioned about trying camber adjustment kit, but I think the problem is more involved. The caster is more of the issue and toe. Camber doesn't cause feathering, it causes increase wear on the inside of the tire. Improper toe/caster is whats killing the tires.

[SteveTheTech]

I agree but most people are not willing to pay to have their tires mounted on the opposing wheels. I remember when the coupe first came out that was the recommended remedy for this issue but at every seventy five hundred miles having to pay to swap tires doesn't seem like much of a fix. The caster factory setting is ~6.5-7 degrees i think, and toe is usually 0 plus or minus 0.02 i think. Alot of the people I see with 17" wheels usually use non directional all season tires (ie Goodyear RSAs) and they have little to no issue with the noise because they are usually cross rotated at every rotation interval. I don't think that anything can be done about the caster angle though without serious changes to the suspension and subframe. A difference would be noticed in steering wheel feel when turning and I don't think it would improve handling enough to justify the cost and time.

[RED_DET]

So then we agree that asymmetrical tires would help the noise issue. Wasn't there a TSB on resetting the toe to max toe in?

[SteveTheTech]

I don't know offhand (I cannot get ASSIST with Vista) I do not however recall seeing a bulletin on that and I have been checking daily for a few years. Do you mean max toe in within spec of zeroing them out? Despite what the ASE tests will have you believe toe will some circumstances wear tires and cause them to feather edge. If you think about it I think it makes logical sence if your center line is 0 degrees and your tires are pointed to the inside would there not be increased rolling resistance and an altered road contact patch? I usually set them to 0 on an alignment its well withing spec, and better for my piece of mind. Yes asymmetrical tires will resolve the noise but they don't have the performance look so many people search for when buying tires.

[RED_DET]

I know Nissan came out with a TSB for the Z, which was setting max toe in within spec of course, I believe it was toe in, dont quote me. Toe out is going to cause inside tire issues, toe in with cause outside tire issues. So moving them in a tad bit may help. One way to find out. I know my g had the issue regardless of what suspension I have put on, oem or otherwise.

[RED_DET]

Some research found this information for the 350z.

Total toe in Maximum(preferred setting) 2mm or .08in. Very important there is NO toe out.

[joe603]

Steve, welcome!

I have an 05 with OEM 19's. When it came time to put on new sneakers (at friggen 13k) I went with Toyo Proxies. They have lasted much longer (17k and probably another 3k left). They are also much quieter and grip better in dry/wet conditions. All-in-all the tire is simply better than the OEM Bridgys.

[SteveTheTech]

Well Hello there this forum is great, I like that people actually want to learn more about their rides or ask questions from other owners hopefully I can use my experience with the company and love of the product to help in any way I can.I know what TSB your talking about that one and the similar one for the Maxima actually fourced many of the dealers to buy the newest balance machines. That was right after I fled to the highline side. I have read some great things about the Proxes sounds like a ideal choice given the suspension setup. I am going to see if my dealer will start stocking these, people are sick and tired of this noise.I am not sure what the cost difference is but I know the Michellins are pretty pricey.Something like that can easily turn people off from the brand due to bad experience.

[joe603]

I got mine at: http://www.tiredeals4less.com/index.cfm

[Q45tech]

If manufacturers could they would sell cars without tires forcing buyers to select and have dealer mount them prior to sale. AS it is they chose fast wearing tires to score well on magazine test and get free of any complaints faster.

Remember alignment is actually MISALIGNMENT sitting still to come into optimum at highway speed when suspension bushings are compressed from forward thrust.

With worn bushings the as new specs may no longer be correct.

[eZg001]

I purchased a 350Z in 03 and was very excited about it. Upgraded the stereo and installed the orange leather upholstery.....thought I had finally found a car that would hold my interest for a couple years. Then the tire wear issue popped up at 6500 Miles......got free front tire..........same issue popped up app 5000 miles later. Nissan dealer even tried resurfacing brakes....nothing. Traded the Z in.....

I found on the internet talk of the suspension being fixed in 06.....purchased an 06 G35 coupe. Still no true fix....

What about aftermarket camber bushings? Does anyone know of a company that sells replacement bushings that might help our obviously flawed suspensions ? I'm putting on Nitto Invo next week and would feel so much better knowing that over a thousand bucks is not going down the crapper in a few thousand miles. Do the aftermarket A-arms like Kinetix and Cusco even really fix this issue? I heard the 350EVO camber arms are great but damn at $850 the should be!

[eZg001]

I called TH Motorsport and Chris reccommended the SPC camber kit. At $399 shipped I guess I'll try it.

[tollboothwilley]

Cusco, SPL, and SPC are good well know and used camber/toe kits for 350z's and g35's

[eZg001]

Yes, thanks, but will they fix the uneven wear? At least the dealership agreed to install the kits....

any advice on Settings?

so far I have found posts stating things like:

1) Key is to reduce negative camber

2) Set to 0 degrees or 'minimum' camber

3) the above post saying total toe in 2mm and NO TOE OUT!

I would love to have exact specs for camber/ toe/have read that caster cannot be changed/etc... I have searched all the G35/350Z forums I could find but have found no more than the above.

Thanks, George

[SteveTheTech]

Here are the alignment specs for a 06 coupe with 18" wheels:All measurements are in Degrees.

Front

Camber -1.3 - 0.3Caster 7.3 - 8.8Toe 0.00 - 0.08

Cross Camber -0.8 - 0.8Cross Caster -0.8 - 0.8Total Toe 0.00 - 0.16

Rear

Camber -1.8 - -0.8Toe 0.00 - 0.22

Total Toe 0.01 - 0.43Thrust Angle as close to 0 as possible

[Sentientbydesign]

Getting your camber around -.5 to -.7 degrees should be good. Having 0 degrees camber could negatively effect handling.

[SteveTheTech]

Agreed a slight bit of camber is ideal. >1degree will wear tires but less than that should not effect tire wear if they are rotated.

[Sentientbydesign]

Can't rotate coupe tires

[eZg001]

should the rear wheels have 0 degrees camber?

[SteveTheTech]

I know they cannot be rotated in the normal sence of the word. Personally I would not mount directional tires on staggered wheels, since I am far to lazy to dismount them and remount them.

Personally I try to set the rear up as ~-0.5 to zero or as close as I can get it . 98% of the cars that I work on are daily drivers and tire wear is the main concern, so it may not be set for optimum handling but it has the maximum contact patch and is still well within spec.

[eZg001]

thank you!!

[maxnix]

I agree but most people are not willing to pay to have their tires mounted on the opposing wheels.

Then these owners will not obtain maximum wear from their tires.

You pays your money and you takes your choices and their consequences.

[Sentientbydesign]

Then these owners will not obtain maximum wear from their tires.

You pays your money and you takes your choices and their consequences.

There are quite a few tires that should not be mounted left to right. My understanding is that the Potenzas have a defined "Outside and Inside"

[awdjdmtalon]

Check out this link. It is to SPC. They now have a camber/caster kit for the front of the G's.

http://spcperformance.com/PROD...&cmd3=

[SteveTheTech]

That looks pretty decent I like that it is fully adjustable and factory ish looking. May not be a badidea if you are sick of the camber.

[awdjdmtalon]

I am looking into getting them. My RF camber is out of spec. It is in the yellow, and my LF is cambered in -1*08'.

[eZg001]

I just had the front and rear SPC kits installed last week. I can't recommend the front kit. The fronts have a problem with the ABS sensor bracket. I had my dealer install and showed them all my research but they have not been able to get the sensor on the right front tire to read correctly. The instructions say to use a non-metallic gauge to adjust to the correct gap between sensor bracket and (not sure what) and the tech said he couldn't adjust the gap.

After two trips to the dealer I still have ABS, VDC, and SLIP lights on. we are going to try and replace the sensor..... then perhaps the original ABS bracket........

I am very frustrated and so is the tech. There are other kits out there like the Cusco and SPL that might be better.

[Sentientbydesign]

The tech can't use a piece of plastic?

[SteveTheTech]

What did you have them replace the one in the pictureonly has upper control arms. I don't see any need to touch the ABS sensor