Is it time for an upgrade to a new car?

It's a 2008 Ford Explorer XLT, curious to know whether it should get upgraded or not.

Added (1). It's not my car, it's my mother's car.

You mean upgrade a working, paid for, low insurance vehicle to a huge debt, high insurance, afraid of getting the first scratch shinier one?

Depends on the mileage, and what if any repairs it needs. And whether or not you can comfortably pay for new one.