Here is the passage again:
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 use Punctuation Rule 9 to fix the problem:
Main clause + , + appositive.
The correction looks 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.
Great choice! You deserve those cookies [even though Glenda had hoped to get them all for herself!]