What are the tire sizes? If it's out of range for stock that's your problem.

 

255×40 18" all around plus spacers.
Stock is 225 frontal and 245 rear.

You sure that's the problem, I know tons of people with aftermarket wheels on Z and they all seem to be without issues.

Also, this issue happened before I changed my wheels.

 

Well, first order of biz: Did you pull codes?

There are times when coincidental happenstances (messing with the panel/wiring) can create issues erroneously and logical conclusions aren't always correct. Pulling codes will eliminate other possibilities.

Dark is also possibly correct though; a 255/40 rear tire is still 0.65" shorter than OE 245/45 so rear wheel speed can be reading high, telling VDC the rear end is stepping out. Yes, it happened before the tire change but it's still possible there's a coincidental fault now being triggered due to the tires being new and that alone could cause wheel speed sensor freak out.

Suggest that after pulling codes, if there are no DTCs indicating something like a cam or crank sensor (a very big culprit in throwing VDC/Slip errors), reinstall your original tires (if available) and see what effect that has.

Finally, if that doesn't fix the problem, you might want to check for proper operation of the wheel speed sensors as they can just go bad with no warnings. To check for proper operation of wheel speed sensors, you first check for proper mounting and clearances - they're very small and simple misalignment can throw it off. Second step is a passive continuity and impedance check. Once you've determined the previous two checks are OK, last step is an operational voltage check. Tons of materials available to step you through the process. Pretty much all you need is a feeler gauge and a multimeter.

 

It is my knowledge that a square setup will always upset the VDC system, might be wrong tho.

 

Was the issue 255/40/18 all around? I have a vdc 05 350z and want to get 255/40/18 all around but im getting mixed responses on whether or not it will upset vdc.

 

What's the matter? Responses in your other thread asking the same question aren't sufficient for your desires to run square? Just do it then. You don't need to repost and necrobump old threads to satisfy your desire to run against 20 year old proven knowledge.

 

“responses are mixed”

some people say that tire size is fine, some just say square in general isnt fine. Im trying to see if anyone with specifically 255/40/18 square have a good experience with vdc.

 

My point is you've not explained why you're hung up on this square setup. I don't care what the rstionale is so no judgement; just wondering why not use the single most "advised" and proven setup.

 

So I have a cracked rim and no spare, therefore car is on a jack. I found a decent deal on fitment industries for some Aodhan DS09 Rotary Forged wheels, 18x9.5 +15, packaged with a SQUARE SET of Vercelli Strada ii tires, 255/40/18. All for around 1500$ without tpms sensors. The thing is, I dont think they sell the vercelli tires in 275/40/18 and if they did, I cant stagger it on the fitment industries website. I want to avoid stagger rims in general just for convenience. If I could do stagger tires with the package, I would. But I just need some wheels and tires asap. Just need to know if it will be fine until my rear tires are out so I can replace em with some 275’s.

 

Pick up the phone. Surely that outfit has a phone! Those Vermicelli (or whatever they are called) can surely be substituted with another no name tire if your brand isn't available in 275.

 

They dont have 275/40/18 tires in that price range in stock. Theyre on backorder. I did some research on the Vercelli tires and found out they’re pretty decent for just a daily driving use and also alright for rain. Havent heard anything bad about em.

 

I get that, but my point was that there are probably 10-15 "other brands" that meet the criteria. If you're not going to buy name tires and going economical for daily and rain commutes, there are many other tires that fit that bill. (Heck, even the set of LingLongs - serious - I had on my Z32 were "just fine" for that usage.) The big point is not the cheap vs expensive tires; rather, "why risk VDC issues" using the wrong size when there are same-cost alternatives to be had in the proper sizes?

 

Heaven forbid he listens to people who actually know what they are talking about.

 

I see what you mean now. I just ordered the rims but now I need to find some tires. Ima look around see if I can find some used name brand ones, if not, what “ling longs” woupd you recommend? I dont need em to be good in the snow. Just rain and dry.

 

I just wouldn't recommend buying from FI at all, none of my experiences were positive there.

 

I know you guys already gave me a answer but I need to know this. I just ordered a pair of 265/40/18 dws06+ for the rear. Im running a 9.5” rim square so I would get a 245/40/18 but it would run a bit stretched. Would I be fine with a 255/40/18 for the front?

 

I thought you bought Michelins per your other thread.

In any event, no, 245s are not stretched. General rule of thumb is that a tire size should not go below 90% of the wheel width nor more than 120% over for maximum performance. A 245 tire is only larger by 4mm or 1.6% larger (101.6% of the wheel width). Statistically insignificant where a 9.5 wheel is almost exactly 1:1 and about the ideal size for a 245. That said, you could easily go to a 255 but then you're back to the VDC issue you asked about in a different thread.

I've run 245/40-18 on 9.5s (and 245/35 on 19x9.5) on about two dozen wheel sets over last 15 years and NEVER had a problem with sizing. I've run 255s as well but with 285s on the rear to keep the wheel speed sensors from tattle tailing on me.

 

I did buy michelins but im going to return em once they get here cus the seller accepts returns as long as tire isnt mounted. I went back on my decision because I found out that summer tires could crack if driven in winter (avg 20f at night where I live) so I didnt want to risk that. Im down to buy a 245 but then I feel like most tire places like les schwab would freak out if they saw a slight stretch when I would for what ever reason want a patch. Rn my car has 225/40/18 all around on 18x9.5 wheels and its pretty stretched.

 

How is it stretched when a 245 tire is 4mm WIDER than the 9.5 (241mm) wheel? "Stretch" is the opposite; when you stretch a "too small" tire on a wheel (or normal tire on too wide a wheel).

Did the math for you already.

But here.... as an example: an 8" Touring wheel (yes, 8" rear) mounts a 245/45-18. A "mere" 8" wheel is 203mm and 120% of that is 243.6mm. A 245 is close enough. Coincidence? Don't think so. Nissan specs their tires within specs of the tires and wheels together. 90%, 120%. That's all you need to remember.

So, a 245mm tire on a 241mm wheel, not stretched, not undersized, more like "this one's just right" said Goldilocks the Moocher. (In my version, the bears eat the intruder.)

Mind you, there are lots of weird sizing things in industry. My Benz wears 255 on 8.5 wheel and 285 out back on a 9.5". All good, right? They are within millimeters of the wheel width. Then there's trucks and SUVs where they run, as an example 275mm tires on 7" wheels? And people wonder why their trucks don't turn when they turn the steering wheel. The tires wanna jump off the wheels!

Moral of the story. You're fine with 245 or 255 (barring VDC error) in keeping with the fact that the Z is a sports/GT, not a truck.

 

Yea I just didnt want the rim making hard contact on a bump. So just for clarification, 245/40/18 and 265/40/18 pairs fine with vdc? Based on the little math I did, it looks like it’ll work fine, but I may be wrong.