1999 W210 Motor Mounts - When To Change?
 

I have a 1999 E430 (aka W2100). I have about 145,000 miles. When I brought it in for service, the mechanic told me I should replace my 2 motor mounts. He said during the test drive he felt they were worn. He demonstrated this when I got there by showing me how much the engine was torquing when he pressed the gas while in drive (while pressing the brake). I saw that the engine was torquing (i.e lifting to one side) about 1.25" when he hit the gas.

Two questions.
Does what he show me indicative of worn engine mounts?
What's the downside of not changing the mounts right now?

You can tell the motor mounts are bad by looking at them to see if there is brown fluid leaking from them. Yours are certainly bad at 145k. My w210 vibrated and buzzed like hell and after I replaced the motor mounts you can't even tell the engine is running while in the car.
You probably won't hurt anything by leaving it alone but the car will be much more enjoyable with new mounts. Lots of info on the subject if you want to do it. Took me about 3 hours.