I recently noticed my car was starting to "shake" at upwards of 60 mph. It doesn't do this at any slower, but once I go faster than 60 mph, it starts to shake. The passenger seat moves rapidly in place, and I can feel the vibration in the pedals.

I was wondering if anyone here has had similar problems with a wrx or if anyone knows what the problem is.
Thanks

 

I suggest you get your tires rebalanced, or at least clean them out (ice/snow/dirt buildup can throw them off balance and cause shaking at higher speeds). My 2 cents.

Tim Quinn

 

It happened to me 2 days ago. The car was fine until I
hit 60mph, then it vibrated like hell.
I thought I broke something when I did donut
runs in a empty snowy parking lot.

I stopped the car and found that there was a hugh snow
block in the driver side front wheel wall. I kicked it off and
tried again, The vibration was gone.

I think the tire touched the snow at high speed
and sent vibration to the chassis.