LunchBox20

iTrader: (4)

So recently my Z has started doing this and I'm confused as to why.
Moved to Cali and explored some of the very nice mountain, hill drives, and while driving, the slip light quickly flutters, and it feels like the car is trying to brake on its own.
I've noticed that the times that it does this, I was driving down steep hills.

Only thing recently changed on the car is the 2 rear tires that were replaced on the drive from TX to CA. Though I'm not sure why this would cause the car to act this way.

Would greatly appreciate any help, and thank you in advance

R350Zz33

iTrader: (4)

whats the specs on front and rear tires

LunchBox20

iTrader: (4)

Here are the tire specs
265/35-18
275/35-18

But I've been running this tire size since forever, why all of a sudden is the car doing this. Its like its trying to brake the car itself, as if I'm slipping?

zakmartin

You're probably getting better traction on the rears than on the fronts, so the car is detecting slippage in the front and is tripping your VDC (assuming your car is equipped). It doesn't take much to activate your VDC, which is why unless it's raining, I usually turn the damned thing off. Do your rears and fronts have the same tread patterns?

LunchBox20

iTrader: (4)

Ah this is true, the rear tires are new with only 1k ish on them, where as the fronts are slightly older.
Thought they still have great tread and contact on them. I wouldn't think that would make the VDC activate like that.

DaveJackson

iTrader: (5)

^I wouldn't think so, either... Unless those tires are way off in size (and it sounds like you checked, and they aren't) I don't know.
I have never found the VDC to be overly sensitive like the other poster said, though. I think something is wrong.

davidv

iTrader: (2)

Rear tire circumference is 1.08 percent greater than front. I assume you are running VDC ON.

sw33tz

My car is doing the same thing, I have however put in 4.08 gears, I do have 20" tires on the car with the rears being 10.5" wide. My car will show slip under hard acceleration even if I am not slipping, very frustrating as the car is retarding the throtle.
I need help! Had the car checked and they can not find anything.

LunchBox20

iTrader: (4)

See its not throwing any codes when I used the OBD2 scanner. I figured something would have some up if that was the case, right?

Its scary though when it happens. I could be in a lane next to another car, and then it happend and the car was jerky and it felt like 3 calipers were trying to stop the car, and one wasn't causing the car to wiggle...and at speed thats scary

Shizzmaster2k

iTrader: (7)

Did you have your wheels rotated at all when you had your vehicle serviced last?

LunchBox20

iTrader: (4)

I had the front wheels re balanced, and rotated the tires, and had the new tires put on the rear of the car and balanced.

I've come to the conclusion with the help of another, that the rear tires are sticking, thus making the VDC think that the front wheels are losing grip.

McLovin350Z

iTrader: (16)

any update?
im having the same issue

LunchBox20

iTrader: (4)

It is believed to have been the fact that the rear tires were gripping while the worn fronts were slipping.

McLovin350Z

iTrader: (16)

So you replaced your front tires to confirm this?
I'm having a similar issue so your feedback will be helpful
Thanks

Dragonbreath

iTrader: (1)

An out of wack alignment will also cause this to happen.

And yes, worn front tires and new back tires can (and vice versa) can cause this, especially in sharper curves.