I have a 04 Rx-8 that when you drive faster than 50mph it starts shimming in the front end area. I have had several opinions and still no luck on fixing the problems. I have replaced the wheels and tires. They were spun and balanced twice to make sure and all is good. Alignment was done and all was good. Visually everything looks in good condition. any ideas let me know.....

 

I've never experienced a bad motor mount personally, but going over 50MPH you might notice bad motor mounts more than at slower speeds. Might be a place to check next.
Maybe someone who has encountered this can chime in to clarify my assumption.
But you performed all the basic steps that I would suggest doing....

 

Check the endlinks

 

endlinks on the sway bar??? it wont even do anything if u drive on a smooth road without corning

 

i think it should be an engine mount;

 

thanks for suggestions, you think it may be the shocks getting worn out??