Is 350 Awd Vibration

[Mark1703]

I purchased a certified 2012 IS 350 AWD in May. During the test drive, I noticed a vibration while driving. The dealer balanced the tires, said it road tested fine and I bought the car. It was my mistake not road testing the car again. Since then, there is a "seat of the pants" vibration at 35-40 mph and 70-80 mph. At other speeds it seems to lessen or go away. I had the tires road force balanced twice. I moved the rear tires to the front. Nothing changed and the vibration did not move to the steering wheel. No improvement. The dealer could not find anything wrong. I'll be going back there again soon. Has anyone had similar issues? Are there drivetrain or CV/axle issues common to this model? This car should ride better for the price. I had a 2002 WRX for 13 years and it rode much smoother. This should not be the case. Thanks for any help.

[LEX-SV]

Is car on lowering springs? Some IS awds get this when lowered.

[VBdenny]

Doesn't the car have staggered tires? Perhaps someone along the way decided to use 4 tires the same as they got a deal or whatever.. Not sure if previous models used the staggered setup but? Maybe put the tires sizes on your car on here.

[LEX-SV]

IS250 awd's have square setup, all 4 tires are same size.

[Mark1703]

It has the same factory size tires all around. The vehicle is on stock suspension and wheels. I'm thinking it's a CV issue. The vibration changes when I turn sometimes.

[VBdenny]

Okay, didn't know they were all the same. Mine has staggered tires. 255/35-18 rear, 225-40-18 front.