I am just to old school to go 7500 miles on an oil change.
Lets say 15,000
At 7500 miles it would cost 64$
At 5000 miles it would cost 96$ ( extra 32$)
At 3000 miles it would cost 160$ (extra 96$)
Not checking your oil in between and getting a blown engine or messed up rings.
PRICELESS ...or about 8000$ for a used motor..
But really, Yes, you save maybe 96$ a year but then you damage your motor if you don’t look to see what dirt in the oil. Oil changes make you stop and look at what is going on with the car. Also Construction and or dirt roads have lots of road dust. It does get in the oil. I have seen it. Now for the do-it-yourselfer’s.. I have worked for a few OEM's and have worked with the engineers. ( I am not an engineer) They showed me in the lab....Oil filters really don’t need to be changed every 3000 miles. They are good for 10,000 miles (If not loaded with dirt). and they filter better after 1250 miles.
So for years I have changed the oil every 3000 - 4500 miles (I check the oil if looking and smeeling ok I push it a little), but only changed the filters every other oil change. This not only saves me a little money but it also makes it more of a reason to drop the oil without reason. I even tell me kids when they don’t change the oil like they should.
"You mean you can’t even so down for 10 minutes to undo the drain plug, drain oil, screw the plug in and add oil before you leave!" This was after I found out my daughter went 15,000 miles without changing oil and wondering why the car seemed to not run right?