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2018 Acura RDX required fuel

Can I use 87 or 89 octane for my 2018 Acura RDX? Must I only use 91 octane? Thank you for your response!

Look in your vehicle manual, if it says 91 Octane Required then the answer is yes . Now after the warranty period you might not want to but I would still do so.

I don’t understand why people buy cars that take Premium Only if they don’t want to PAY for premium?


Page 111 of your owner’s manual.

"Fuel Information
Use of unleaded gasoline of 91 octane or higher is recommended.
• Acura recommends TOP TIER Detergent Gasoline where available.
• Do NOT use gasoline containing more than 15% ethanol.
• Do NOT use gasoline containing methanol.
• Do NOT use gasoline containing MMT.

We recommend quality gasoline containing detergent additives that help
prevent fuel system and engine deposits. In addition, in order to maintain good
performance, fuel economy, and emissions control, we strongly recommend
the use of gasoline that does NOT contain harmful manganese-based fuel
additives such as MMT, if such gasoline is available."

In the Engine information section in the back of the manual it states that 91 octane or greater is required.

If I’m not mistaken your engine requires premium fuel, so you should only use that.

Many people assume that there is money to be saved by using lower octane fuel, but if you do the math you’ll see it’s not so.

Let’s say you drive 15,000 miles a year and the car gets 22MPG. Assuming a price difference of 40 cents between regular and premium, using premium over regular will cost you $22 per month more. Is $20 a month is nothing but pocket change when you’re talking about a $35,000+ car.

Factor in that regular may lower your MPG slightly and there’s really no savings at all.

Thank you.

It seems like the % difference in cost between regular and premium isn’t as much as it used to be 20-30 years ago. 87 out here in San Jose today runs about $3.50/g, 91 is only $3.70; that’s less than 6% higher for the 91. octane.

That’s a bargain. Regular here is about $2.60, premium is $3.10, almost 20% more.

I do have a question about the RDX - it has the same engine as the Accord V6, same torque, only one hp more (279 vs. 278). Regular is specified for the Accord. Hard to see why the RDX requires premium.

I have just used the mid grade on all my V6 Acuras and never had an issue. I don’t use regular but the premium here at the Mobil station is non-oxy for boats, lawn mowers, and off road use.

I have had 5 or 6 late model MDX’s and now have my second RDX. They will run on regular, mid grade, or premium. I believe that milage is higher with premium, having checked full tank to full tank. All of my 20 plus Honda’s and Acura’s seemed to get better milage after a few thousand miles. YMMV.
This vehicle came with a full tank of gas. Ask you salesman what grade they bought.The window sticker sttaes that the RDX comes with a “full tank of fuel”.