Not all gasoline’s with higher levels of detergents have elected to join Top Tier… For example, BP, which is not listed as a Top Tier gas, was named in a media report as having detergent levels comparable to two Top Tier gasoline marketers …
It remains however that oil companies PAY to use the Top Tier label, and some simply refuse… That does not mean, that their gasoline is inferior in any way… many companies use the same types and amounts of detergents as do the Top Tier brands and have wisely or unwisely choose not to pay for the label Top Tier…
Bottom line -- buy the least expensive national brand available, and don't waste money on labels and, avoid stations with old rusty, leaking tanks that may contaminate the fuel with water and dirt…
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