VDC kicking in with new rear tires
 

I put on a set of new rear tires (same size as OEM) and did not replace the front tires. Now my car feels like I'm driving on balloons in the rear. I understand the 500 mile drive-in period, but I got myself almost killed today cruising at normal speeds on twisty back roads when the VDC started to kick in. The car feels like I'm driving on ice. Did some research and found out that this apparently is/was an issue with G35 and 350Zs as well. Anyone else had similar experiences? The car now is basically not safe to drive IMO.

damn be safe man! Sorry i cant help you im a newb at tire stuff!

I also had this Problem when new tires were installed on my G35c. Back end was wild. After the break in period the tires "reacted" normally and this "problem" was not an issue. :tup: Give it time it will go away once they break it and make sure the air pressure is correct.

That is wild....I didn't know new tires did this to our cars.... Yikes! Drive safely out there.

What tires?

sounds like new tires call for standing burnouts... :-D

Agreed:tup:

Did you buy the same brand/model tire as you have on the front?

And yes, obviously you need to clean them with a good burnout... :)

New tires are essentially green and do not develop maximum grip until they have been through several heat cycles. Having new, green tires on the rear can create an oversteer condition. Be aware that mixing different brands/models/sizes of tires can create significant changes in the behavior of your car that may not resolve themselves with heat cycling. Also note that identical tires can preform differently depending on the tread depth. The tires with the shallower tread typically deliver quicker response and greater traction. On a low to medium performance vehicle these differences may not be especially significant but on a car with the quick responses of the 370Z it has the potential to be significant.

^^that, spot on, well said.

New tires need to be seated properly. Avoid sudden acceleration and braking until they settle. This means no burnouts! Avoid gravel and rough roads and you should be fine after a few miles. The tire manufacturing process sometime leave lubricants on the tires and needs to be worn off. The tires are essentially made up of different compounds that don't have maximum grip until properly broken in.

I have a feeling he bought crappy tires

You may indeed have the wrong tires for your needs, refresh my memory, what exactly did you get and how do you intend to use (summer, winter, track etc.) them?

I got the Hankook v12 EVOs. Did research on them before I bought them and the reviews were generally very good. This morning I have been driving for a few hours (since 5am - this issue became an obsession last night) and the car seems to settle in. Drove with the VDC off for a while and cruised at legal speeds on interstate and back roads. The oversteer issue that Guard Dad was referring to is certainly the case. I have a feeling that the added tread and maybe softer sidewalls add to the looseness of the back-end. I'll keep driving for a week or so and if things don't improve we'll have to get a set of front tires I guess.

This is what Road & Track thought about the EVOs - they mention that they are somewhat soft and I tend to agree. Obviously the price does not reflect the 275/19 size.

“Deceptively quick” is a good summation of the Hankook Ventus V12 Evos because they often didn’t feel as strong as they actually were, particularly in the dry. Their fourth-place autocross time wasn’t spectacular, but they did outlap the benchmark Michelin PS2s. Geswein said the Hankooks felt “somewhat soft” and “imprecise,” although they were forgiving, yielding consistent laps with no surprises. Despite that feeling of softness, the V12 Evos somehow managed a second-place skidpad run of 0.93 g and were above average in braking. Hankook just launched a new extreme-performance Ventus R-S3 model, which wasn’t available in time for this test but likely has sharper dry responses.

In the wet, however, the V12s were as sporty and connected as they come, with grip second only to the PS2s’ and the best braking. The Hankooks were extremely consistent, likely because they were so well-behaved, which made them easy to drive quickly. Subjectively, they felt the best around the track, even though their time trailed slightly behind the Dunlops’.

With above-average wet and dry performances, and tying for quietest on the street loop, the V12 Evo is an impressive and well-rounded summer tire. And, at $106, it’s a bargain, too.