OK so I have to replace the tranny mounts on my car and I'm looking up the prices on the mounts and I see that there are 2 different kinds. 1 is a solid and the other is hydraulic. What is the difference between them? And do I need both kinds or just 1? I need to replace them both because apparently they are both shot.

 

just one trany mount. the poly ones transfer vibrations really bad. just get the stock one. its like 10 bucks. while your under there replace the torque arm bushing/mount with a poly one. they work great for that.