got this thread from 6mt.net
http://www.6mt.net/forum/g35-sedan/2...er-speeds.html
i notice this on my 6mt also, at first i thought it was just me but after reading that thread it seem to be a known problem on some of the sedans.
anyone else have the same issue here? it gets very annoying and i swear your holding the steering wheel straight and it drifts slightly to the left n right.

 

I describe my car as being somewhat "darty". I had attributed it to the alignment issues (due to lowering) and the wider rubber. Its almost like it catches a small road groove or something and kind starts heading that way...

As an engineer, I realize roads are crowned, and you would EXPECT the car to move slightly towards the low side of the road. Its not always the case though. I didnt think much of it though, keeps me from falling asleep!

 

I have taken several long Hwy trips and can't say I noticed this problem. It does wander some depending on the road regardless of speed. Wide front tires are always grabbing lines and ruts and will make the car pull in various direction... this is normal for wide performance rubber.
I don't know how the G35 alignment is setup.. but the more "neutral" setting for the alignment specs.. the more the car will wander but will behave better on a road course when pushed.

 

It's tramlining normal for performance tires, you should try new 3 series BMW that thing is scary way to sensitive.

 

I figured it was normal for my setup... thanks for reaffirming that!

 

I noticed movement as well, but I don't see it as drifting. It's more like the car is rutting on the highway. the indentation from the most commonly driven part of the road is slightly sunk in, I think because the trucks cause most of this and they have a wider wheels, the car tends to want to fall into either the left or right channel and that's where the pulling comes from. I notice that if you ride with one tire in the center of the lane and the other on the outside of where the ruts are (by the line) then the car is smooth as glass and no drifting. if you try and stay in the lane the car flip flops back and fourth between ruts in the road.

At first it was a little uncomfortable, but I'm starting to get use to it. Mainly because my previous cars had a bit of play in the steering you didn't feel the wheel pulling in your hand, but this car is amazingly (in a eye-popingly good way) tight. So it's something I can live with.

Once you realize where you need to travel in a lane to avoid the ruts, you'll see the car can do 100mph strait as an arrow.

 

I'm glad This thread came up. After putting on the new boots I noticed it can pull pretty hard to the sides sometimes. Figured it was due to the new width but wasn't sure it would be that much. Definately worth it though.Never had a car with high performance low profiles before.And besides, now it drives like my truck with it's 35's.

 

im glad its not just my car. i just got a lil over 1000 miles on it but im sure ill get use to it after a few more hundreds.

 

I assume all your tires are inflated properly to the same level? Also, many, if not most roads, are not perfectly flat. They are designed to be able to dissipate water more efficiently to get water off the roads. In these roads, your car would drift to where water would normally drift.

 

i check my tire pressure and its on 35psi, i believe thats normal on our car.
you made a good point there about how the road are made this way, however i did own a coupe before and it never drift this way.

 

Yes- roads are crowned at 2.08% typically. My car will sometimes move against the normal road slope. I am pretty sure the tires are inflated to even pressures, I will check it out to make sure though, good call-