Date registered: Mar 2012
Vehicle: 2009 ML320 Bluetec, 2013 Tesla Model S 85
Location: Madison, AL
Mentioned: 0 Post(s)
Quoted: 18 Post(s)
"Top Tier" is a marketing gimmick. A salesman observed some brands have higher detergent levels than others and has found a way to collect fees from oil companies by getting manufacturers to recommend (but not mandate) his Top Tier trademark.
The EPA mandates minimum detergent levels with which your engine has to be able to run the 8 years or 100,000 mile Federal emissions warranty, or Mercedes-Benz has to fix it for free. All EPA testing is performed using this minimal spec fuel.
As for "peppy", log your MPG. Literally, write down every fuel purchase, source, price, gallons, odometer, trip meter, etc. It takes about 5 tanks from one source to get a good measure for comparison. If you get better MPG with Chevron and its cost per mile is better than others, then by all means continue to use Chevron.
If you can not measure a benefit/advantage then it doesn't exist.
The Trip/Fool Computer display is only good for relative comparisons. M-B has done something funky as RESET on mine always starts at 25 MPG so I'm still questioning its benefit for relative comparisons.