G35X snow traction problem

[rlavender]

My wife reported our 2007 trying to fishtail in slippery (icy or snow) conditions in 2008, but I pretty much ignored it. We live near Denver but don't drive much in the snow. I bought new GY Eagles last summer. Today we are stuck in a hotel in Grants, NM after encountering light snow and some freezing on I-40. The car would not drive in a straight line, trying to make the rear end slide from side to side. Even at 40mph I had to continuously "saw" the steering wheel to correct for the rear end trying to break out. It got so dangerous we found a hotel and hope for better conditions tomorrow.

Anyone with similar experience or suggestions?
Thanks
Rich

[audtatious]

Which GoodYear Eagles are you running?

I've noticed that manufacturers like putting "all season" on tires even if they are only good for 2.5 seasons.

[kmckis1029]

my g37x was fine with almost 1 foot of snow and plenty of ice patches... I was running the tires in my signiture. I didnt experience any fish tailing... it was actually kinda amazing how in control i felt.

+1
So i agree with Audtatious, got to be your tire choice.

[RED_DET]

Turn the SNOW MODE on.... it will help by limiting the amount of torque especially in starting from stopped positions.

Seems people seem to misunderstand the AWD system in the g35/g37. The under normal conditions is mostly RWD and then the ATTESSA system takes control when the rear wheels begin to slip. Your VDC should also be kicking in to limit torque to the wheels if you are to the point of the rear end fish tailing.

[kmckis1029]

i never had my snow mode on last year when we got snow... still no fish tailing with snow mode off...

must be flooring the G in the snow lol... but even so when i played in a empty parking lot in the snow/ice my car was fine... never felt out of control... this is VDC off in the snow with a g37x

it was actually kinda hard to get the car to spin out... took almost WOT to get the AWD to let me slip and slide...

id love know what tires the OP is running cause id know to steer away from those tires lol

[rlavender]

Thanks for the responses so far.
Correction on the tire type - they are Michelin Primacy MXV4 with 16,000 miles and good tread (for what that's worth with all-season tires). I found reviews that are very poor on snow, but our experience was the same on the OEM's that came on the car (can't remember what they were).
My understanding is the "snow mode" merely starts the car in second gear from dead stop, and has no other function or effect while driving.
Also, my understanding is that VDC, when sensing loss of traction, gently applies brake to that wheel, thereby transferring power to the oposite side.
Could it be that the VDC braking is too hard on the slipping wheel? Would this cause the opposite side to unbalance the car and fishtail? Then when that wheel lost traction, would the reverse happen, and fishtail back to the other side? I'm recreating in my mind the effect at 40mph, having to correct steering direction every two seconds. It was scary as hell.

[RED_DET]

VDC doesn't gently apply anything in my experience and most of the time I drive with it off, especially in dry conditions. VDC will limit power incredibly once a certain amount of traction is lost. In your case there could be several factors as to why the car behaved the way it did. Tires play a huge roll, icy roads make things even worse.

Snow mode limits the amount of torque applied until the car reaches a certain speed and no slip is detected.

[WAldenIV]

If I recall correctly, the X starts with a 75% bias towards rear wheel drive up to 8 miles per hour at which point it switches to RWD unless wheel slip is detected. Snow mode forces the car into a 50/50 split until about 16 - 20 MPH.

[kmckis1029]

yeah VDC is kinda invasive to me also... im sure you will notice when it kicks in... im still leaning torwards your tires being the problem. they best AWD systems are still only as good as the tires.

yeah snow mode makes your car 4wd up to a certian speed and makes the throttle less sensitive, cool feature to have. i switch on snow mode when i park in grass or gravel so i dont kick up dirt/rocks or mess up the grass.

[rlavender]

I want to thank you all for the replies, ideas, and suggestions.
The cause of the problem was found to be extreme negative toe-in on both rear tires. I have to thank the techs at Mike Ward Infiniti in Denver for figuring this out.
This is a great forum and I appreciated the help.
Rich

[audtatious]

Interesting. The tires seem to rate well so it was strange. Toe issue makes sense.