Do you really need to use 91 octane in the 3.5 Nissan Altima?

I get that question a lot. Your car and mine are designed for the good fuel. If you drive like grandmom. Lower octane might be fine. But it says premium fuel reccomended on the gas door doesn't it? Try this test measure the next two tanks of regular gas milage is the key. You'll see low octane does not allow the fuel system and spark control run for maxium power. So you will push just a little more on the accelerator. Premium fuel however is what the 9.0 to 1 compression engine was designed for and you might find 3 more miles to a gallon running it. Thus saving money over the twenty gallon tank. Owners manual section 9 page 2 says (91 octane) and 20 gallons 60 more miles or 8 dollars might make up the difference in price. 20 cents x 20 gallons or just four dollars more per tank And you thought you were saving big money. And costing mileage lost $4.00

You do not have to use 91 octane in this car.... That's just the reccomended.... It will run fine with 87....

87 octane is fine and recommended

you can use 85 if you want as long as you are not pulling big hills all the time. you have enough computer control ont he engine to use what ever you want for a shot period of time. i run 85 all the time in a 03 mitz and not problems what-so-ever

Seriously, read your manual. Or if you lost it, download one. It'll tell you all that stuff about fuel.

Yes, it will give you transmission problems and the warranty will be voided. good luck.

it shouldn't do anything. regular should be fine. thats only if you want the best performance

it isn't necessary but it is recommended