BPalladium

According to the dealer, Acura "recommends" premium fuel for the 2016 RDX, but it will run just fine on regular, albeit at some loss of performance. Having tried a couple of tanks of regular, I can attest that it does run well on regular and I personally can't see any performance difference. I'm wondering, though, whether there's a downside to this. Acura also stresses the use of fuels with advanced cleaning additives. Are these added to regular fuel as premium?

hand-filer

https://acurazine.com/forums/perform...remium-859183/

Rocket_man

Here we go....

Doubtit

Again. ....

CoachRick

I'll be leaving soon enough; but the same discussions are taking place in the Fiat 500 forum...87 minimum, 91 recommended. Seems like plenty of folks over there do what is being done with the RDX...plenty of 87 being run, plenty of 91-93 being run, most folks not able to tell a difference. IF the little 1.4l turbo in the 500 suffers on 87, that's a problem...darned thing only has 160hp anyway!!!

I mentioned in another thread...last week a local Top Tier station had the 93 for SIXTY CENTS a gallon more than 87...THAT'S a pretty good hit! I hope that doesn't continue. Oddly, diesel is now very close to the cost of 87...last year it was a dollar more than 93 !

Joe Las Vegas

Please moderator delete this crap. If you wanted 87 you should have bought a Hyundai. There is a HUGE thread on this already.

carbonTSEX

Should have bought a Honda.

BPalladium

I apologize for missing the previous thread, which is very helpful. My bad. For the record, I never said I wanted to use 87. My DEALER suggested that I do so. I was surprised by this. You don't need to lecture me on how stupid it is to spend $45K on a luxury car and then try to save a few cents per gallon gas. My instinct is to ignore the dealer's suggestion and conform to the manufacturer's recommendation (91). My belief is that it's wise to do so because higher-octane fuels contain better cleaning agents.

sumoto

While I'm not sure they're actually better cleaning agents, I do believe there's a higher percentage of them in the premium fuel, especially in a top tier brand. Considering this, It might well be good insurance over the long haul for less engine maintenance.

CG_RDX

Maybe we can steer this to a different topic within the same vein.

I was considering buying a demo/loaner vehicle. However I question whether the dealership itself or the drivers of loaners shelled out for premium gas.

I know that if I were to buy such vehicles I would still use premium but would the damage have been done getting a "new" car at 4000+ miles?

Comfy

Loaner / demo / rental should not matter. If the vehicle manufacturer recommends it, I would use premium. If its not your car, consider the few cents you paid as insurance for a good cause. I don't expect others to do so but hope many will (just in case I am the one buying the same pre-owned vehicle from the dealership- of course for a killer price discount).

ceb

What do you put into a loaner before you return it? Whatever board members put into the cars is obviously better that what the average driver puts in.

I'd opine that 99% of the driving public who are NOT on enthusiast boards use the cheapest swill possible - that no-name gas that's 2 cents cheaper than everywhere else.

BTW, there are no differences in the types or amounts of additives between premium and regular gas. If it is a top tier station then they regulate the additives based upon the TT requirements. If they aren't TT, then each company decides on what additives to add above and beyond those mandated by law - but they MUST add the same amount to all grades of gasoline.

I would also opine that most dealerships only use regular gas - regardless of what is recommended or required. I frequent a station that is also used by the dealer for their demo cars. I've seen RLXs being filled with 87. The tank the dealership uses that is located next to their service bay (for that first "free" tank) is labeled as 87 octane.

bzb123

After perusing the official thread for this issue, I feel only answer is- midgrade, which is 89 in my area. Close enough to the recommended; cheaper than premium, which is 93 here.

CoachRick

Confirming the SIXTY cents difference between 87 and 93 at a different station today. THAT will add up if you have two vehicles(or one) and drive ~30k miles a year between two people. Eight hundred bucks is nothing to sneeze at!

Murrow

Either you can afford to operate the car or you can't. Even at $.60 a gallon difference (which is nowhere near the norm anywhere I've seen), I don't care. If $800 is too much to allow you to fill up with what the manufacturer recommends, then buy something else. No shame in doing so. And as far as I'm concerned, mid grade is a massive cop out. You don't get the octane OR the savings.

As for what dealers say or do, dealers are dirtbags. You can't expect them to do the right thing and fill the tank with what they should. Hell, I've found I can't even count on them fill my tires to the correct pressure.

tmux

The sensors will adjust to protect the engine from knocking.

Performance difference might not be noticeable especially if you aren't pushing the limits. The more interesting question is, are you seeing a difference in fuel economy with 87? And if so, does that cancel out the savings.

TacoBello

Read: "I should have bought a Hyundai! "

hand-filer

They recommend premium to make you feel like you bought something special and that's the simple truth. It's just a Honda motor in a different wrapper.

Comfy

The RDX is already "special". I don't know how a different fuel would make the RDX "more special".

yesrdx

Compression ratio seems to be a big part on whether an engine requires regular or premium gas.

A list of Honda's V6 Engine in different models and their fuel type requirement:

Honda Odyssey V6 with 10.5:1 compression ratio - regular unleaded
Honda Crosstour V6 with 10.5:1 compression ratio - regular unleaded
Honda Accord V6 with 10.6:1 compression ratio - regular unleaded
Honda Pilot V6 with 11.5:1 compression ratio - regular unleaded
Acura RDX with 10.5:1 compression ratio - premium unleaded
Acura MDX with 11.5:1 compression ratio - premium unleaded
Acura RLX with 11.5:1 compression ratio - premium unleaded
Acura TLX with 11.6:1 compression ratio - premium unleaded

CoachRick

As I've mentioned many times, in many Volvos and in my RDX, I've run countless tanks of 87 along with countless mixed tanks ranging from mostly 87 to 100% 93 and not one tank showed discernible decreases in performance or mileage. In fact, my 'best' tank of fuel in the XC60 was 87 purchased in Mississippi for a trip back to Texas. I checked those numbers a few times to make sure the dramatic increase in highway mileage wasn't miscalculated(and, no, there was NOT a tailwind on that leg of the trip).



Dude...DW's FIAT has the same fuel recommendations as the RDX. Our Miata wouldn't run worth a nickel on anything less than 91. Do you have a point?


We've owned plenty of vehicles that cost between $45-50K over the last 15 years. IF I could discern a difference in performance or mileage by running a higher octane fuel, I certainly wouldn't mind paying for it.

tmux

Mucn appreciated, though there are conflicting reports such as from the thread linked earlier in this thread.

To have a direct comparison, however, you would need to make the same trip, same time of day/year, same weather, same traffic, etc etc etc. That's not feasible so it's good to aggregate a lot of data points. I just stumbled across Fuelly.com, haven't dug around it much but they might have some good data.

Mechanically, something's gotta give if the timing is tweaked to avoid pinging. If there really is no difference, then the car mfgers could be playing it ultra safe with the recommendation for 91. However, some people out there do report a difference. For me, for now, I'll put up with the extra 20 cents per gallon. I try to save compared to my 87 days by spending the extra minute to check gas price buddy on my phone for the best deal on a good brand.

MetalMan55

When we purchased our '15 RDX AWD Tech in March, the sales guy at my dealership actually recommended using 87 octane.

I have 3600 miles on the clock and am averaging 24.3mpg in combined city/hwy driving.

Best I've done is 29.6mpg on a round trip to Cleveland traveling 70-75mph.

Around town, I'm getting 21.5-22.5mpg.

Performance has been more than adequate....no pinging or knocking.

FWIW......

thoiboi

Majofo

CoachRick

Don't know who that guy is...I don't get out like I used to.

Majofo

He's the head of the central octane commission

Majofo

He's also the former head of the can am well consortium. He ran pipe across the whole northern and southern hemisphere.

TacoBello

So you obviously had to test that theory on your Miata as well, I see.

I hate to say it, but the price of your vehicle has little to do with what fuel you should be using

If you want to use regular, by all means do so. But don't mislead others down your path of misinformation, telling them that it is 100% ok to do so.

Majofo

Apparently CoachRick wants to run diesel.

CoachRick

Never told anyone to do anything...simply relating MY experience over 15 years driving vehicles with 'minimum vs recommended' fuel standards...and the attendant cost differences.

CoachRick

Not a chance! Diesel was running over a dollar MORE per gallon than 93 petrol until just a few months ago! Those poor diesel drivers were being taken to the cleaners!!! Oddly, it is almost exactly the price of 87 around here lately. That is WAY strange!

Majofo

preserved for the annals..

Vlad_Type_S

iTrader: (3)

Please consult my sig for relevant scientific conclusions on the subject.

Majofo

I think you should update your sig

Vlad_Type_S

iTrader: (3)

yeah me too, but just when i thought it wasn't relevant anymore............

CG_RDX

So as I left my dealer when I bought my 2015 Acura RDX, I asked my sales guy if my "free" tank o' gas was going to be regular or unleaded. He just immediately answered that premium is just recommended and left it at that. So that was his cute way of saying regular. Getting the car at 246 miles, I guestimate that gas had to had been filled no more than 3 times with regular. Following the advice of other posters, and with gas prices falling, I have filled up with good ol' 93. I didn't wait until I got to empty to do it...

I figure once I get around to between half a tank and a quarter, I will just fill up with the good stuff and spend just as much if not slightly more to fill up as if I went empty and fill up on the 87 stuff. 93 octane does burn cleaner and that has gotta be good for overall maintenance. Because really, if the price of premium is really a concern for folks, than there are much cheaper alternatives...whether it is a regular Honda or a Hyundai. I almost went the Santa Fe route myself until I smacked myself back into reality...

Macau Park

I switched to regular in my civic Si at 70k miles, and after ~15k miles I got some mild knocking and vibration, then my motor mounts wore out. Not saying the gas causes that, but it definitely caused some knocking.

High compression engines call for premium fuel, and I would run the premium. If you want to save on gas, should have bought a CRV touring. It gets great mileage and runs on regular. I am the type that prefers to speak softly and carry a big stick though.

hand-filer

The 2016 Honda Accord has the same compression, torque output, 1 more HP output and requires regular gas. Why?
Refer to post #18 for the correct answer.

Majofo

While the engines might be nearly identical, premium is recommended because you're not driving a low-profile car on wagon wheels. You're driving a brick that is several hundred pounds heavier on wider tires.