5.7 liter engine - Octane question

One of my cars has a 5.7 and I only use premium gasoline in it. My boyfriend tells me I can use 87 octane and my car won't know the difference. True? What's your opinion? Am I wasting my money on premium gasoline?

For you car experts out there, what would suggest?

TIA!

Call your dealship service department.

Engine size doesn't dictate the use of premium or not,if you have the owners manual check that,if premium needed a lot of modern cars say so at the gas filler,or call a dealer and ask the service dept.,telling them the exact engine you have.

The engine will run with any pump gasoline. If it's a sportscar then you probably want to use the higher one, because you will get more performance (horsepower) with the higher octane gas. If your car has a computer engine mgt system it should adjust itself to run on lower octane. Try the lower octane - if you hear pinging then you need to go back to the higher octane. I'm glad I get to use the 87 - it cost ALOT less the the premium.

there have to be dozens of expert reports about this on the new google machine the kids are using...


if its an everyday car thats approx 1995 or newer, i dont think it matters.

and check if your manual requires it or recommends it. recommend is just another word for optional. any service dept will just default to whatever the manual says, though you may get a personal anecdote from some.

I had a 5.7 liter engine in my Tahoe when I had it and it ran great on regular unleaded. I ran a tank of premium through it every few months just to clean up carbon deposits. Man that was a great engine...never had a problem with it.