Usually seems to be at about 45 mph
Tire cupping can be caused by worn out shocks or struts, weak springs, bad wheel bearings, loose parts, defective tire, or a tire out of balance.
A tire cupping can be caused by tread being lost. A tire cupping means that it should be replaced as soon as possible. You do not want a cupping tire to be used while you are driving. Air can escape and cause a flat.
At high speed vibration usually its tire balance. Have your tires rotated and balanced.
No, tire cupping is not normal. It is normally caused by worn shocks or struts. It may also be caused by other suspension problems.
Only if you feel vibration at speed, or if you get a tire plugged or patched. Naturally, when you change tires
Cupping is caused by lack of regular tire rotation and proper air pressure. Check the owner's/service manual for frequency of tire rotation and correct air pressure for your vehicle.
Over inflation of tire. - lower your pressures.
bad shocks
Common cause could be a tire out of ballance or a bad tire, meaning the inside is separating. If your tire is out of balance the vibration you get will be at a particular speed usually over 45-50 mph, depends on how far out of balance the tire is. If you have a bad tire the vibration may start gradually then get worse as you speed up. Note: These are the common causes that I am famillar with. The best thing to do is take it to a mechanic to be checked.
Yes, it can but cupping can also have other causes. Over inflated tires can tend to bouce more, especially when combined with weak/worn shocks or struts. When tires bounce cupping can occur when the tires strike the road. Cupping can also be caused by the tire/wheel assembly being out of balance (which can also cause the tires to bounce). Cupping is just one of several types unusual wear on tires.
Improper rotation or worn shocks or struts
This can be a warped rotor or tire out of balance. If it only happens when braking it is a warped rotor.