Sudden strange vibration and helicopter noise

I have a '99 Toyota Sienna minivan. We’ve had it for a bit over a year and have had no problems. The tires were new when we got it.



Yesterday I was driving home with my 3 kids on an expressway at about 65-70 mph when I started to notice a little vibration in the steering wheel. It was a quick vibration. It didn’t really feel like what I’ve experienced with an out-of-balance tire in other cars I’ve had in the past. My first thought was actually that it was the road surface–it’s a newly resurfaced road. But I figured out pretty quickly that it wasn’t that.



I got off at the next exit and looked at the tires, thinking one might be going flat. I didn’t use the tire gauge, but they all looked reasonably okay–nothing obvious there. So I got back on the expressway to limp it home. Of course the shimmy started back up, and got worse. It also started to sound and feel like there was a helicopter hovering directly over my car. By the time I exited the freeway the noise was so loud that my kids were complaining.



I made it home okay, although by the time I got there the helicopter noise and feel were happening even at speeds as low as 30 mph.



I’m going to go out and check the tire pressure just to make sure I didn’t miss something obvious there. My husband will be getting home from a business trip today, and I’d love it if I could at least tell him that somebody gave me an idea of where to start looking for the problem.



Any ideas? Thanks.

Don’t Drive It!

I’m glad to hear that you got home. You could have a bad tire (I know, they were new). Tires can have defects along with anything else.

You could have a suspension/steering, wheel/wheel bearing, etcetera problem.

Until you find out what is wrong, whether it is minor or a serious problem, don’t drive it. This could be dangerous.

This car should get up in the air so that the underside can be safety checked.

CSA

Besides the good suggestions by the previous poster, make sure the lug nuts are tight on all four wheels.

Ed B.

I am betting on a tire failure. The first thing I would do is jack up each tire and spin it while looking for excessive runout. Then run your hand over the tread and sidewalls to see if there are any lumps. You can also substitute each tire with the spare to see if the noise goes away.