CAR SHAKES LIKE THERE IS A LOOSE TIRE ...MORE NOTICED AT LOWER SPEEDS AND SMOOTH ROAD....SEEMS TO STILL HAPPEN WHEN SHIFT TO NEUTRAL. ANY IDEAS? ALIGNMENT..BERRINGS? STRUTS???

After you check the lug-nuts, with the engine not running, grab the top of each wheel and push and pull to see if you feel any looseness. It could be many things. If you don't feel a looseness. Take the car to an alignment shop and have them look it over.

I agree to all of the above . Mostly towards the bearings. When my bearings went I could also hear a light humming/grinding noise. As tony said any movement in those wheels, get it in soon. Either case has very dangerous outcome so don't procrastinate about it. One more thing that I have seen that would have symptoms like that is a seperated tire tread or bad tire. So if your tires are worn out and have heavy mileage on them that could be something to look at as well. Discount tire or the like would tell you for free if your tires look bad by pulling in and asking.

Also, when you just put on any tire to the vehicle, it will not handle properly whatsoever. always follow the specs for the car ( usually the tire specs are on the sticker with the VIN). It always helps also to make sure you have the same tread and cut/ thickness. I really hate driving around with a tire that is thicker than the other. If you cannot tell it is your tire, it's a long day. Am in junk yards all the time taking off brand new parts. And I see countless times, just any tire make/ cut, etc. No WONDER they are in the junker!!