Hey guys! Ive had my IS250 rwd for a year now and I love it, its given me to issues so far. I'm having an issue that I think might be related to a mount and would like some input, so here are the symptoms..
When coming to a complete stop weather its hard or normal braking I get a slight shake and it feels like it might be related to a transmission mount because the vibration comes through the center armrest....than, while stopped my steering wheel and pedal have a intermittent vibration. Those are the only symptoms I have so far and the vibration isn't horrible, I just want to get it fixed before it becomes a real problem. Also, this doesn't happen every time I brake and the car has 93000 miles on it.

That isn't a common issue, but I've read of members having replaced their mounts to fix other such vibration or rattling issues.

Let us know what you end up doing.

Sure this one isn't the infamous carbon build up issue? If the engine itself isn't running smooth, new mounts may in fact mask the actual problem.

Has it had any service work done related to carbon buildup? When was the MAF cleaned last, plugs replaced, things like that?

If you feel a vibration during braking it's probably your rotors. Had the same issue with my GS (and still do from time to time). Motor mounts will smooth out your transmission shifts, but if you feel the steering wheel shake during braking only and not at other times that sounds like what it is. You may also feel a shake at highway speeds from time to time it just depends.