octane

BatTruk · Jan 23, 2018

i am using 87 in my 18 rebel this was told to me by dealer...should i change?

Graygoose · Jan 23, 2018

89 if a Hemi

BatTruk · Jan 23, 2018

5.7 mds so ok ty

Graygoose · Jan 23, 2018

welcome!

grizzstang · Jan 23, 2018

There are 400 threads on what octane to use in your Hemi.

If you look in the owners manual it will tell you 87 to 89 is OK but "89 is recommended for optimum performance" and that while operating on 87 "hearing a slight knocking sound from the engine is not a cause for concern". Funny, it would concern me but what you use will depend on how you interpret that.

BatTruk · Jan 23, 2018

that was very helpful ty...now my lazy ass needs to read manual

huntergreen · Jan 23, 2018

I have run 87 and 89. I don't see a difference. Engine runs fine, no pinging and no difference in mpg. Some have posted the 89 improves performance when towing heavy.

Trooper2 · Jan 23, 2018

Dont know if its bad for the truck or not but I tend to switch back and forth. Here in VA 87 is 2.35 and 89 is 2.65. I'm a numbers guy so I will break it down. I drive a lot and use 42gal of fuel per week. My weekly fuel cost is $98.7 on 87 and $111.3 on 89. Over the course of a year running those numbers I will spend $655 a year more using 89. Thinking practically if I go to the store 3 days a week and spend $5 on a drink, snack, or some other ******** that would be $780 during the course of a year.

Like I said I switch from time to time. Usually I run 89 because the manual says its recommended. My goal is to make the truck go 250k miles on the same engine. I have 13k on ot now and I took delivery September 1, 2017. Anyway I know my gas miliage wont be great just cuz I run 89, I won't be able to flip off the electric cars any quicker, but I get a little peace of mind knowing I'm protecting my investment a little more. Many people run 87 and never have an issue. Although I'never seen anyone run 87 for the life of the truck with over 150k and not have an engine issue. Back to my point and I'm sure some will disagree but if you take care of your truck which means 89 octane it will take care of you. That $12 more a week is better then $5000 for a new engine at once.

Good luck.

Graygoose · Jan 24, 2018

Detonation is a bad thing, why I want all the power my engine has.

Ramnewbie · Jan 24, 2018

I run 93 in everything except my lawn tractor. Maybe it's overkill but I don't have to worry about pre ignition or the computer retarding the timing to run the lesser gas. Just makes me feel better.

Sent from my XT1650 using Tapatalk

Rampaige · Jan 24, 2018

I notice my RPM gauge idles much smoother with 89 compared to 87. And that makes me feel all warm & fuzzy inside......so i continue to keep using 89.

Sent from my iPhone using Tapatalk

69GWC · Jan 24, 2018

Rampaige said:
I notice my RPM gauge idles much smoother with 89 compared to 87. And that makes me feel all warm & fuzzy inside......so i continue to keep using 89.

Sent from my iPhone using Tapatalk

Same with mine

huntergreen · Jan 25, 2018

Haven't noticed smoother idle between different octane. Could it be the quality of the fuel ?

MT Hillbilly · Jan 25, 2018

Only fuel here that does not have ethanol is the high grade, I run it in every thing. I feel even more important in small engines, working hard.

Sawman · Jan 29, 2018

I run 91 premium

Jlh hemi · Jan 30, 2018

Trooper2 said:
Dont know if its bad for the truck or not but I tend to switch back and forth. Here in VA 87 is 2.35 and 89 is 2.65. I'm a numbers guy so I will break it down. I drive a lot and use 42gal of fuel per week. My weekly fuel cost is $98.7 on 87 and $111.3 on 89. Over the course of a year running those numbers I will spend $655 a year more using 89. Thinking practically if I go to the store 3 days a week and spend $5 on a drink, snack, or some other ******** that would be $780 during the course of a year.

Like I said I switch from time to time. Usually I run 89 because the manual says its recommended. My goal is to make the truck go 250k miles on the same engine. I have 13k on ot now and I took delivery September 1, 2017. Anyway I know my gas miliage wont be great just cuz I run 89, I won't be able to flip off the electric cars any quicker, but I get a little peace of mind knowing I'm protecting my investment a little more. Many people run 87 and never have an issue. Although I'never seen anyone run 87 for the life of the truck with over 150k and not have an engine issue. Back to my point and I'm sure some will disagree but if you take care of your truck which means 89 octane it will take care of you. That $12 more a week is better then $5000 for a new engine at once.

Good luck.

I ran 87 in my last hemi and i drove it to over 200k miles. Only issue i ever has was it busted a valve spring in the motor at about 190k. Replaced them all with 6.1 hemi springs and was good to go. I sold the truck to a friend of mine and he is at about 250k on it now. If that doesnt blow your mind this will....its still on the original tranny never been rebuilt and the fluid was never changed in it either just topped off when it got low.

Trooper2 · Jan 30, 2018

Thats pretty awsome Jlh! Regular just went to 2.50 a gallon here. Been doing a little more reading and I think as long as I get my fuel from Exxon, Mobil, Costco, Shell, Sunco, or other reputable place I should be good.

OFw Kalli · Jan 31, 2018

I run for normal daily ride 87 octane and that's ok.
If I would haul heavy stuff, I would change one or two filling before to 89 octane.
More is unless. Higher octane is not a better, only other gas.
How a guy wrote in a German car forum.... That's like a t shirt in size M, L and XL. The XL has not a better quality.
And "size M gas" works fine because the hemi can "wear" both sizes M (87) and L (89).
XL (92 and more) are way to big.

I have not noted that I need more gas with 87 octane compared to 89 octane. All runs good, quite and smooth.
And if anybody hear a nock noise, they should check the anti nocking sensors. This sensors note way earlier than a human ear a beginning of nocking and set the motor parameter to prevent nocking.

Graygoose · Jan 31, 2018

Detonation kills pistons. The knock sensor will retard timing until it stops. If it runs better on 89, you get optimal timing. Sure you can run on 87...with less timing, equals less power.
Now using 91 or 93 in a car that recommends 89 is a waste. But to use less than stellar gas, is killing power essentially.
Id personally rather be ready if I climb a steep mountain, or mash the gas to pass someone, etc than wait to refill with better gas. :naughty:

Rampant · Jan 31, 2018

If you stick with any Top Tier gas brand, you'll be fine. Here is the official list of them.

octane

Member

Indecisive Car Owner

Member

Indecisive Car Owner

Senior Member

Member

Senior Member

Member

Indecisive Car Owner

Senior Member

Senior Member

Power Wagon

Senior Member

Senior Member

Junior Member

Junior Member

Member

Member

Indecisive Car Owner

Senior Member

Similar threads

Forum statistics

Share this page