What may be the cause and what is the estimated cost of repairs? Thanks.
Hi there. Most of the time, a high speed shaking such as this is caused by tire imbalance. It can also be caused by a tire that is failing. I would typically recommend having the tires inspected and road force balanced by a tire shop.
If the tires are fine, then the suspension and steering parts will need to be checked for excessive wear. If those are good also, then it may have an axle that is failing or an engine mount problem. If you need to have the steering and suspension inspected, consider having a certified mechanic, such as one from YourMechanic, come to your home or office to take a look at it for you.