89 octane recommend, does it really make a difference?

[TangoFoxtrot]

I live at a high altitude, 5500 ft, so with the thinner air I can use 87 without any detonation. I have run multiple tanks with 87 without any knock, but a slight loss of power, which is why I do the half tank dance. Of course at my altitude I'm already losing about 15% of my horsepower so the blend helps keep it from additional power loss.

I'm at like 600ft, LOL, but I've never noticed any knocking on 87 ever. But others have and I can only speak for my truck. I will say this, I highly doubt all the contractors and regular folks driving around in rams are using anything but the cheapest fuel they can find. I am willing to bet most ram hemi owners are completely clueless as to the recommendation of using 89. I'd run 89 if it was only 10cents more though but, 93 is cheap at COSTCO, lower than most charge for 89, same with Sams club.

 

[4x4Laramie]

I'd run 89 if it was only 10cents more though but, 93 is cheap at COSTCO, lower than most charge for 89, same with Sams club.

Costco has the "Top Tier" gasoline while Sam's does not

 

[TangoFoxtrot]

Costco has the "Top Tier" gasoline while Sam's does not

I actually did not know that! I really didn't know if either actually were. I gave up on top tier only a few years ago, but I do stay away from the stations with no names and racetrack. I actually know two people that have received bad gas from QT, which surprised me.

 

[theblet]

I’m at 0 ft lol

 

[Begrenzt]

HSKR
Could you elaborate on getting better mileage with 89 over 93? Not trying to argue, just learn.

Drove to St Louis over the weekend and got 18.79 driving 73 mph most of the way. I noticed that the dash MPG reporting seemed to drop significantly when I went to 75.

Looking at heading to the west coast in June and trying to figure most economical driving speed and gas.

Thanks in advance

 

[HSKR R/T]

HSKR
Could you elaborate on getting better mileage with 89 over 93? Not trying to argue, just learn.

Drove to St Louis over the weekend and got 18.79 driving 73 mph most of the way. I noticed that the dash MPG reporting seemed to drop significantly when I went to 75.

Looking at heading to the west coast in June and trying to figure most economical driving speed and gas.

Thanks in advance

You need to understand octane ratings and how they work to really be able to understand why you will get worse gas mileage running a higher octane than your computer is tuned for.

 

[BigD]

People talking about keeping the truck 10 yrs & 200,000 miles worried about blowing their engines with 87 octane gas is comical. U will have thousands of dollars in electrical issues b4 u ever blow your engine. The 5.7 Hemi is one of the most reliable engines ever made. It's been around a long time. The main problem with all new vehicles these days is electrical. Too damn much fancy gadgets. That's why I trade in every 5 or 6 years before i hit 100,000 miles & maximize my trade in value. Also if u by used, who knows what gas was used or if they even changed the oil ?

 

[HSKR R/T]

People talking about keeping the truck 10 yrs & 200,000 miles worried about blowing their engines with 87 octane gas is comical. U will have thousands of dollars in electrical issues b4 u ever blow your engine. The 5.7 Hemi is one of the most reliable engines ever made. It's been around a long time. The main problem with all new vehicles these days is electrical. Too damn much fancy gadgets. That's why I trade in every 5 or 6 years before i hit 100,000 miles & maximize my trade in value. Also if u by used, who knows what gas was used or if they even changed the oil ?

Really hasn't been around that long. Original was first used in 2003/04. Been several changes over the years. When compared to other iconic engines like the SBC and 318/360 which were used for almost 40 years.

As far as fuel goes, it really comes down to whether you are willing to sacrifice performance and engine life for short term fuel cost savings. Much like a catch can, the average owner would never care about the slight benefit when they can save money short term.

 

[MarvsAMartian]

I got a check engine light and knocking when I put 87 in mine. Been using 89 since. Could be a case of bad gas but I'm not willing to test it again.

 

[SD Rebel]

Probably bad gas, because even the manual states 87 is acceptable. I've run all the octanes and honestly not noticed a difference with any of them. However, since 91 Costco is cheaper than everyone other stations 87, I just use that.

 

[bwsRam19]

believe it or not, you stand a better chance at getting good quality 87 than you do higher octanes because 95% of the people on the road are using 87, so that means its most likely fresh gas your pumping.

 

[TravisJ]

As far as fuel goes, it really comes down to whether you are willing to sacrifice performance and engine life for short term fuel cost savings. Much like a catch can, the average owner would never care about the slight benefit when they can save money short term.

It isn’t short term savings though, it is long term savings and equates to thousands of dollars.

 

[HSKR R/T]

It isn’t short term savings though, it is long term savings and equates to thousands of dollars.

It's short term savings on a tank by tank basis, as that's how you determine what you are willing to spend. And for it to become "thousands of dollars", it would have to be very long term. At 50k miles, using a 15mpg average, and 20 cents per gallon difference (even though it's not always that much) it's only $660 in savings. That would be over 3-4 years of ownership for the average owner. Would have to be close to 100K miles to get over $1000 "savings". And that's just a per gallon estimate saying you will get the exact same gas mileage on each octane. Should get bettwr gas mileage, long term, using the recommended octane, so that cuts into some of the "savings" from running cheaper fuel.

It's up to the owner though. I choose to use the recommended octane, or better, for my truck because I care about it enough. Also same reason I run a catch can.

 

[Fuzznutz]

believe it or not, you stand a better chance at getting good quality 87 than you do higher octanes because 95% of the people on the road are using 87, so that means its most likely fresh gas your pumping.

Very true! Common sense sometimes knows more than manuals.

Sent from my SM-A505U using Tapatalk

 

[TravisJ]

I wish 89 was 20 cents more around me. It’s a 40 cent difference in my area.

You can call it a short term savings, but any notable problems from running 87 (if any) aren’t short term problems. A tank of 87 doesn’t blow your engine. Any major issue probably wouldn’t be seen till well after 100k miles. The cost of running 87 versus 89 should be looked in that same light.

What someone wants to do is their own choice, their truck...but $10 at the pump really starts adding up quick.

 

[HSKR R/T]

Very true! Common sense sometimes knows more than manuals.

Sent from my SM-A505U using Tapatalk

Believe it or not, most gas stations only have two tanks, and mix 87/91 to get 89. So that kind of throws that theory out the window

 

[HSKR R/T]

I wish 89 was 20 cents more around me. It’s a 40 cent difference in my area.

You can call it a short term savings, but any notable problems from running 87 (if any) aren’t short term problems. A tank of 87 doesn’t blow your engine. Any major issue probably wouldn’t be seen till well after 100k miles. The cost of running 87 versus 89 should be looked in that same light.

What someone wants to do is their own choice, their truck...but $10 at the pump really starts adding up quick.

In my area, it's usually only a 10 cent difference.

 

[Fuzznutz]

Believe it or not, most gas stations only have two tanks, and mix 87/91 to get 89. So that kind of throws that theory out the window

Interesting!
What do I know

Sent from my SM-A505U using Tapatalk

 

[HSKR R/T]

Interesting!
What do I know

Sent from my SM-A505U using Tapatalk

That you can take pictures?

 

[bwsRam19]

Believe it or not, most gas stations only have two tanks, and mix 87/91 to get 89. So that kind of throws that theory out the window

And......if the 91 isn't fresh gas.....your mixing old gas in, so that throws your theory out the window