Hi all, after trading in my 08 IS250 for the 06 IS350 i notice that my car feel floaty left to right on the road at high speed. It is a common problem with the 06 or should i go have it check out?

 

What brand/type of tires are on the car? Also what is the air pressure?

 

What size shoe you wear.

 

Was the alignment and geometry checked?

 

I have 2 Bridgestone EH33 Turanzas for front tires and 2x Continental Extreme for Rear. All at 34 psi.

 

i'm thinking i will have to do the alignment and balance since i got off the dealership.. don't think they even touch it

 

I assume you mean ER33. The tire pressures are a bit low unless you're looking for performance. Ideally you want 38-40 front and 36-38 rear unless you do more freeway driving than city, then 36-38 front and 38-40 rear.

The dealership most likely don't know much about alignment anyways, you probably would not bother bringing it to them. Most likely they are going to just make it in the green and call it good.

You need to bring the car to a shop which specializes in alignments, frame and suspension systems.

 

yeah, pressures are low- and the fact they're not even the same tires doesn't help either.

 

The 08 steering was recalibrated to feel tighter than the 06-07. This is more than likely why it feels different although I have yet to drive a 6/7 myself.

 

Floaty feeling is also a sign of shocks going bad.

 

I would first check the alignment! But it may also be the torque of the car lifting the front end slightly making the front end a bit lighter, there for looser steering input.

 

Running different types of tires like you are can throw off the car as well. Depending on the stiffness of the sidewalls between the two. The Contis are really mushy, the bridgestones will be a bit stiffer. I would recommend never running different types of tires like this.

Think of it this way...on your left foot you have an Air Jordan, on your right foot you have a Brooks Running shoe. Your gonna walk a little funny and it won't EVER feel right to the point where you have to compensate on how you should walk.

Your car reacts the same way, and even more so at a higher rate of speed. If your feeling floaty, most likely it is the squishy Contis on those back wheels letting the rear end slightly move from side to side. Uping the pressure in the rears may help stiffen the ride a little. 34psi is a little low for all of the tires and will give a soft ride but could also add to the floatiness (if that's really a word)

Hope this helps!

 

after you do all of that maybe try gettign the IS-F steering damper it maty help a little....it did for me

 

The only time I felt "floaty" on the HWY was when I inflated my tires to like 38 psi all-around (BFG KDWs). Lowered them back down to 34 psi all-around...FIXED. But I do think it is your tires and the fact you are running two types and two different tread patterns.

 

Live with it if you're not willing to change tires to be the same. Balance and alighn because my friendly stealership missed that and I now have 1 bald tire..