Yes, some tires are not made properly and the rubber can separate causing the tire to be out of balance causing a vibration. This is somewhat rare but it does happen. Most tire vibrations are caused by uneven weight in the tire or wheel combination causing the tire to be out of balance.
If the tires are properly balanced plug tires should not cause a vibration.
Yes.
Yes.
tires. possible 1 or more has belt separation
Not all Altima's vibrate. If the car is vibrating, it may mean that there is something wrong with the tires.
You will feel the car vibrate around 50-80 MPH
The tires could be unevenly inflated from one another. Also you could have 'shimmy' where your brakes or axle cause the car to veer slightly, which could also affect tire wear and steering, alignment and vertical balance. Start with properly inflating your tires, then get them rotated and balanced-- with any luck that could be all that you require.
drive shaft could be out of balance or tires could be out of round
When one drives a car with tires that are not aligned correctly, it can cause premature wear on the tires and will cause the car to start drifting uncontrollably.
If your car is shaking it could be poor suspension alignment can cause a car to shake and vibrate, and other possible causes are bent or worn suspension parts, old tires, bent wheels and bad brakes. If your car sounds especially rough at speed, the problem could lie with the car's spark plugs and wires. Spark plugs fire more frequently the faster you drive, and the engine will sound rough when they begin to fail.
You have one or more tires out of balance.
Only if the tires were made of molybdenum.