Hi! I bought a hit rx8 about a year ago and I fixed it up. It's 2007 with 39,000 miles and is automatic. I noticed this today that when I put it in drive and stand still it vibrates.. but when I put it in neutral or park or reverse it's perfect. Could this be bad spark plugs or bad engine mounts? I'm a really paranoid person, someone please help me out! I also recently did my engine oil change and my transmission oil change.

 

My first guess would be motor mounts.

 

That's what I'm thinking!

 

Will it damage engine/transmission if I don't change them for awhile?

 

I guess it depends if they are bad, how bad?
If it's just a little vibration, probably won't hurt for awhile.
If they're totally broken and the engine is bouncing around, then fix it.

 

The rear view mirriors shake just a little bit. The shaking goes away once I start driving.

 

You could always get a Prius

 

Not now, but i think its better to change it sooner than later, because it will get worse and worse and you might get problems when it vibrates more than usual.