What makes my X5 dance?

[Clutch]

Hi all. I finally got my first long road trip in my 2006 X5 4.8is - Washington DC to Buffalo NY and back on a variety of road surfaces, but mainly good old PA & NY interstate. During these combined 16 hours, I think I have confirmed my X5 dances across the road, and I am pretty worried about it.


The car has a lateral (side to side) sway that comes and goes. I cannot reproduce it at will. The effect can be quite dramatic at times (verging on dangerous) with the vehicle pulling quite strongly left or right. The car can be all over the lane with a mind of its own. Note that when this happens the steering wheel is not being pulled or turned – it stays straight but the whole car just veers off. This is my first car with all wheel drive, DSC, and air suspension. However, our 2005 X5 4.4 drives perfectly normal. I have wondered if the rear tire tread is acting to pull the car? It is pretty radical tread with strong diagonal grooves that I think may grip just the right way and pull the car sideways. (I have included a picture.) I bought the car with just 22,600 miles on it, and yet it had non-factory rear tires (Toyo Proxes) but factory front tires. I don’t know why they were replaced (under warranty maybe?) I now have only 26,400 miles.

I took the car to the dealer (under warranty until 10-15-10) and they said the problem was "not found". However they admitted their test drive was limited and maybe I should take the tech out for a long drive. I do not think it is due to grooves in the road - at least non ethat I can see or notice. It happens in a variety of different places and speeds.


I did a search and found a similar post from 9-23-09, but no definitive answer.


So my question to the experts is: "What can be making my X5 dance like this?" Is it the radical new tread on the rear, the air suspension, a suspension problem, or something else broken somewhere? I'm at wit's end but strongly suspect the tires. I'd like to get this figured out before the warranty expires. A tire swap test would help, but hard to arrange with someone. Any advice or comments you might have would be greatly appreciated. Many thanks in advance.


PS - BTW, I got an amazing 18.6 MPG with two adults, baggage, AC on, and running 80 MPH almost all the way. I thought I was dreaming but checked the math. I am impressed!

[Weasel]

The tire swap test can be easier to set up at the dealer if they have either some old take-offs that will fit or a used car/trade in with wheels that will work... Just can't use another customers wheels obviously unless consented to.

Also, if the front and rear tires have different enough rolling diameter (which changes with different brands etc.) the x-drive transfer case can cause a unsteady wobble type feel in the drivetrain. If this is suspected they can simply unplug the VTG actuator motor and drive it to see if the feel went away. But that can usually be felt around 35-45 mph as well.

[X5Matador]

I had the same thing happen a couple of times when I had Toyo Proxies on my X. They were ready to be replaced when the "dancing" occured.

[FSETH]

I had Toyo Proxes on my 19 inch sport package wheels for over 40,000 miles and never felt any "dancing". They always tracked true.

[jst2878]

sounds like the valleys in the road where every other tire drives on. I get it all the time. its just the road

[amacman]

like jst2878 says
we call it tramlining , if you looked close up at some parts of the road surface you will see valleys formed by slow moving heavy vehicles . on some parts of the road they are in straight lines , other parts mainly uphill there are certain sections where more powerful or lighter trucks will pull out to pass the heavy in front , this is where your car will dance most as it tries to follow the valleys .
my X5 had continental sports tyres on 20 inch rims when I bought it and these were really bad at tramlining so I fitted a set of 4 toyo proxes st and the car now suffers very little tramlining making any journey more comfortable .
it`s possible your mix of tyres is making the issue worse .
I fit 17 inch winter wheels with 235 / 65 R17 tyres and these have no issues so one can assume the wide tyres on wide rims are trying to ride the lip of these valleys .
if your 4.4 has 18 inch or larger wheels you could swap wheel sets between cars to see if the 4.8 still dances or if the 4.4 develops the issue with those tyres .
just my 2 cents opinion , hope it helps .

[Naz24]

Originally Posted by jst2878

sounds like the valleys in the road where every other tire drives on. I get it all the time. its just the road

especially up here in central to upstate NY, the weather really gives the roads a beating. I notice some of the same on the road surfaces up here.

[Ben2.0]

Not sure your experience with wide low profile tire wheel combo but especially side to side the road tends to pull you around quite a bit because you have so much tire physically on the road coupled with the very a short small sidewall. Try running max air pressure in the on a new corvette or viper and take it for a quick run down a heavily rutted interstate its alot to deal with. Im pretty sure if the dealer was able to give you a set of 18 or 19in rim/tire combo your problems would not be happening.

[thedweeb]

Originally Posted by FSETH

I had Toyo Proxes on my 19 inch sport package wheels for over 40,000 miles and never felt any "dancing". They always tracked true.

[chilliwilli]

Originally Posted by jst2878

sounds like the valleys in the road where every other tire drives on. I get it all the time. its just the road

This...

It will handle differently than the 19's i assume you had on the 4.4i. With such large & wide tires, they often want to follow any grooves in the road...my solution is to drive faster