Thanks Ozarkdude. More good and soothing advice, certainly! We've had some weird weather here, first lots of snow, muck and chunk ice (maybe it is in fact a chunk of frozen mud / ice in the inside of the wheel), then a significant ice storm, rain, and then a 55 degree day today with mud and melting going on.

To the technical aspects of the problem: As I mentioned, and as you point out, it almost certainly does not seem to be the engine. Sure, the car's motor, with the mileage, has some rough spots, especially now on startup as I am told the "lifters" are starting to fail. Again, I am a newbie, green and wet behind the ears to the technical world and I will freely and humbly admit I have no idea what "lifters" are. But, that said, once the car warms up for five minutes and the rpm's at idle are what appears to be approximately b/n 5 and 10 (app. 750), the car pulls out and shifts through its gears as if it was brand new. I went out earlier and took it out again but did not go above 50. Almost no shaking. However, there is some of what I would call the same exact shaking, but at a very subtle measure. Hardly noticeable and if I did not drive this car everyday and listen to it and feel it intently every second it is running on the road, I would not notice this. Again, no doubt about it at 60 and greater though. Man, feels like if I were to continue going faster it would bounce off the road. It is strange though, because for all that vibration, it does not seem the steering or the actual ability to handle it is compromised, just that this vibration is critical to the infrastructure of the vehicle. I am inclined to unfortunately resign myself to the "drive shaft" theory, since again, it seems like this vibration (which is very long, as opposed to short, in frequency - if that makes any sense) does not affect the steering, handling, suspension so much as it does just the core (even the frame I would say) of the car itself. Thanks again for responding.

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CJTucker