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Dodge Durango - adding new gas to old gas

My car has a 12 month old quarter tank of gas. If i fill it up with premium will it start? Also already cycled some bad gas throughbthe system ran for about 60 seconds or less and not well . thanks - matt

It shouldn’t have any problematic effect given the nature. If you are truly worried you could find the fuel line and pull it from the secondary filter and (if you’re willing) blow the gas back into the tank, or just push some gas out until your comfortable with it.

Fill upthe tank with fresh premium and drive the truck. The longer you do, the better it will run. Re-fill the tank again with premium and you should be good to go.

If premium works, no need to use it at the next fill-up. It makes sense to use it the first time to ensure the octane of the old/new gas mix is high enough. But regular will be fine after that.

And I’d get it from one of the “Top Tier” gas stations, they have more detergents in them.

Why premium gas?

Regular gas has just as much detergent in it as premium gas.


Well, according to Tom and Ray, premium gas can have more additives, not that they’re worth it for normal driving:

And ExxonMobil says their premium has extra detergents:

"Exxon and Mobil Synergy SUPREME+™ Gasoline

Our premium grade unleaded gasoline was formulated with a higher octane level and additional detergent additives to meet the demands of some of today’s most advanced engines. It generally has an octane level of 93 but is blended with an octane level of 91 or 92 in certain areas of the U.S. "

Alright! I’m firing it up then! Thank you!