He estimated his car to have burned around 5,300 gallons of gasoline . This was based on the fact that it got 23 miles per gallon locally and 30 MPG on the highway.

The odometer approached 135,000 miles. The visualization of that number provided some sense of joy. Like no matter...

My  Hyundai has about 132,000  miles on it. Given its  MPG around 23 in the city and 30 on the highway and my driving patterns, I estimate that this car has now burned roughly 5500 gallons of gasoline . 

That's a lot of gas! And calculating by the average price...