I have a 2005 G35 w/ Auto Transmission. With the VDC on if I go around a turn at high speed, the VDC is kicking in way too soon. I don't think I am anywhere near slipping and but the slip light will flash on and the car will jerk/dive. I can turn VDC off and go through the turn much faster and and isn't slipping at all. Is the VDC THAT conservative or is there something wrong with it?

 

Did you change any of your tires recently?

Lou

 

It is a new car to me. It has Michelin Pilot Sport tires on the front and Toyo tires on the rear. The fronts are about half worn, the rears are in really good shape.

 

VDC is really conservative. Better safe than sorry.

 

The Michelins are probably original, the rears are replacements. With a performance car like we have, you should try to keep all the tires the same maker and model. Performance tires have different handling characteristics, and behave in different ways. IMO, that's what's happening here, the tires are gripping at different times in different ways, sort of hard to explain. But, the VDC is smart enough to see this, and give you a warning that something is wrong.

Lou

 

When the VDC kick it it is usually in right hand turns. When it kicks in it almost feels like the left front tire is almost locking up or braking very hard (this happens if I hit the brake or not). So I turn off VDC and it doesn't do this as long as I am off the brakes but if I even slightly touch the brakes in a hard/fast right hander, I get that same feeling, like the left front is locking up. The fact that it is so different from left to right makes me think something is wrong with it.

 

The VDC is kicking in because of the mismatched tires. The system is that sensitive. I had the same problem when I tried to just replace the rear Michelins. I had to go back the next day and replace the fronts with the same brand and model as I put on the rear.

 

BINGO! I agree.

 

Yes, because Toyo's have better grip than the Pilot Sports, arguably because of their style, but most definitely because they have more tread on them because you said the Toyo's in the rear are new.
Your front tires are slipping and the VDC is trying to intervene to prevent it. Your front tires are worn, and your rears are new. They're going to have different grip characteristics because of that alone.

 

Maybe, but the fronts are not THAT worn. I really doubt they are original tires (39,000 miles and more than half tread). Also, I notice that the VDC only kicks in on right turns. I can rail on a left turn and it is always perfect. When I go much slower in rights turns the slip light comes on. Also, as I stated earlier with VDC off just lightly tapping the brakes in right hand turns will cause the same left front lock up feeling I get when the VDC slip light comes on. I am not saying different tires aren't causing the problem, but there is something wrong with the huge difference between left and right turns. The left and right front tires have similar wear and the same air pressure.

 

I'm stumped then. I don't know what to tell you. The Infiniti dealer is going to point out that you've got different tires on there, so that will be a dead end. What else can you do but change the tires?

 

I agree. Change the tires and see if that helps.

 

I have the same EXACT problem as you... the VDC kicks in only on right corners... mostly higher speed sweeps (+40mph). I live in Dallas so I have not had the opportunity to turn if off and test it... no margin for error. However, I am experiencing the same problem. Seems that the VDC kicks in when not really needed... I know that there is no way a G35C would slip going around a 45 degree in dry weather at 50mph.

In terms of tires, I just got this car three weeks ago and it has Pilot Sports all around... two are brand new and the others are not new but have plenty of tread.

I went to the stealership (car is under warranty) and of course they said they could not replicate the problem.

I want to get this resolved before trying to put a bandaid on it with new tires or suspension mods.

Any ideas?

 

Exactly. sometimes it is not very fast of a turn at all and it will kick in. I don't think a slick on a wet road would be slipping at these speeds, let alone a Pilot Sport with more than 1/2 tread left on it. If your problem is the same as mine, with VDC off you will only have a problem if you lightly tap your brakes while in a right hander. You lightly tap your brakes and it feels like the left front really grabs (just like it does with VDC on).

 

FWIW I just changed my rear wheels to wide Z rated 18's with very low miles on them but have stock 17's in front w/ 50% tread left on them. Long story short, I didn't have the right size tire iron for the new wheels, used a socket that was a little too big (enough to get them on but slipped trying to get them off) then realized they were way too wide for the front.

The handiling is great, very noticable difference in responsiveness, it feels faster and more planted. I ripped it around hard turns right and left this weekend with VDC on and no problems at all. I'll try getting a spacer for the front but I'm driving it like this for the time being. Not sure what this means but certainly my traction is way different front vs. rear and I don't have any issues. Do you have another set of wheels you can swap to test it? Wife's car or something? Just don't want you to spend a wad of cash prematurely if that's not the real issue.