Two weeks ago I replaced my 040s with S-03s. 225/45 front and 255/45 rear. A couple of days later I read that my tires are out of spec for the required min/max difference in diameter front to rear to the tune of 1.1", more than anyone else has successfully managed. The warning that comes along with this spec is that VDC/ABS may not function properly, and sure enough, my VDC is not coming into play in a timely fashion. It comes on too late in that if I was REALLY out of shape in the rain or accident avoidance, I'd be in trouble.

Being the **** douchebag that I am, not to mention stupid, I've decided to eat the 255s and order a proper set of 245/45 rears for $405. Hopefully I'll be able to turn those 255s around in no time since they've only a few hundred miles on them.

Take this as an important lesson. Even "oldtimers" and those who've had their cars for quite a while are prone to making stupid mistakes. I drive the **** out of the car regularly and plan on tracking it this year, and did not want to take a chance on everything not working as it should. In my quest to get an extra 10MM in tread width, I've f**ked myself out of $400 in mod money. I've yet to explain this to the wife.

 

Out fo spec by 1.1 inches? What am I missing here? The 255s are only 3 tenths of an inch larger in diameter than the stock 245 rears. The stock Touring differrential between front ant rear is .8 inches. Do you mean that going up to a 1.1 inch difference caused the problem? That means Nissan is cutting it pretty close from the factory.

What is the spec'd min and max difference?

joe

 

The spec'd min and max is no less .5" and no more .7" I think that's extreme, but the difference in the S-03s is 25.9" F and 27" R. Skidazzle commented on the late VDC when he drove my car the other night. I've confirmed this and I'm actually more concerned about ABS failure and flat-spotting my tires.

 

No. That's the most asinine part.

 

I'd sue what does nissan think people will actuall read the manual or something? The nerve of them. J/K

Too bad your wife will understand nobody's perfect.

 

Just get a set of 255/45 for the front and then you'd cure that understeer problem. Who needs ABS on the track anyway. Oh, you'll need a new set of Volks of course. But for a $1999 and change you can solve that problem too.

No seriously, we have to find a way to run the same size tire on both ends. All the M3 guys do it. Anythiing else is maddness due to the lack of ability to rotate tires.

 

Impulse buy. Went in to get the 245s, chose the 255s w/the 45 profile. D'oh!

 

Remember this:

https://my350z.com/forum/showthread....highlight=s03s

It's been FIVE MONTHS on this set up, and have had no such imagined problems. The VDC is very annoying, comes on much too soon for my liking, on the street, and changing the size did not make one bit of differrence.
The third motion I make in the car after starting and buckling up, is turning off the VDC.
How can you really believe that .03" can make that difference?!?
IT DOES NOT!!
Did Nissan tell you not to do it? Think hard on this.
Dude, don't believe the snake oil that others will try to sell you, your gut feeling on the tire choice was a good one, believe me, BELIEVE YOURSELF!

I spent 81/2 months deciding the best tire choice, starting on Jan15th when I ordered the car.
I had those S03's in my garage since July of last year, staring at them, salivating at the sight of them filling out the 8.5" rims unlike any 040, and waiting for the car.

Track
Chrome Silver
S03's
K&N
Earthing Kit
White Finisher

 

Re-read your quote and think about what's different between your car and mine...

8" vs. 8.5" rims.

Do you think I really want to do this? I don't, but there is a noticeable handling deficit in my car now. I f**ked up and now I'm going to pay the price.

BTW, interested in a spare set of 255/45s? I'll let 'em go cheap.

 

Seriously Droid,
Am I reading your specs right? So the stock diff of .7 (or .8) depending on which calculator you use (for the 225/45 and 245/45) is right, or over the upper limit?


I'm glad I got 9's in the rear with my new wheels, plan on using 245/45-18 front and 275/40-18 rear. With these being the same diameter, am I screwed?

 

I know the cars with 17's don't have VDC but we do have ABS and the difference between front and back is only .39 and no effect on ABS. You could be out of that tolerence with just thread depth difference. I think there is more to this just have to figure it out, but since I don't have VDC I guess I wont worry when I put on my 18's and go with a 235 and 255/45 combo.

 

That is what I posted before, just treadware could put you out of spec if that were true. I think the "late VDC" is just psychological because you are looking for a difference. It's no different than all the people that put in an intake and their "butt dyno" tells them there car is now faster.

 

I agree with you and westpak here. The tolerances can't possibly be so tight. Treadwear would make a lot of difference over time. All of this just doesn't feel right. I'd want some empirical measure on the late or malfunctioning VDC. I also plan on getting some 18" (Track sized) wheels and tires for my Enthusiast. I can't believe that would throw off the TCS and ABS systems...

 

Man, you are stupid!

 

Droid man, that sucks dude. I'm curious though, where did you see that spec on the diameter difference range? I'm also having a hard time believing that your 1.1" diff is going to affect the VDC, but I'm no engineer. I feel bad now that I didn't let you know how my tire choice turned out. If you remember, I also went with the S-03s, with 235/40/18 and 255/40/18. The difference in diameter there is only .6". Anyway they work great, and VDC seems to work the same as before. I don't know if you should give up just yet. If you do have to replace the tires, you might try and find some 235/45 for the front instead of replacing the rear. Just a thought.

 

Since when do we need special circumstances to laugh at you???

 

Did you try turning VCD off????????

Its sad that people rely on things like VCD to get them out of hairy situations. I have never had it, and most of the cars I have owned didn't even have ABS...yet I have never been in an accident, and never had a close call that was my fault exept if I was doing something stupid in the first place.
What ever happened to gut instincts?

 

I use VDC in the wet. Of course I turned it off, but when I want it to work I want it to work right, not three seconds later.

This is a non-issue now. The new tires arrived this A.M.

 

About the tires. I'm interested.....

 

Well thanks for the vote. Lets just think about this, first I looked at the manual and no where does it tell the mechanic to verify tire size when checking out any of the systems.

Second lets think of how the sensors pick up the wheel speed. They do not adjust to go to the outer edge of the newly installed tire they are fixed on the same spot measuring the same section of the wheel at the same location which will spin at the same speed whether you have a 17 in wheel or up to a 20 in wheel therfore no systems will be affected other than your actual speed versus the speed the speedometer thinks you are going.