Here is the original item:
Even though the windows leak and the paint is peeling, Georgette loves her
old pickup truck. The vehicle that has dependably taken her everywhere since
junior year of high school.
You chose to connect the appositive to the main clause in front, like this:
Even though the windows leak and the paint is peeling, Georgette loves her
old pickup truck;
the vehicle that has dependably taken her everywhere since junior
year of high school.
Unfortunately, you do not use a semicolon to connect these two parts. Review the rules.