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THEPRFCT10 11-27-2010 09:20 AM

What Octane?
Heard mixed info about recommened octane for the Hemi...just wondering what you guys are using and why? Dealership said Hemi is built for 87 but they recommend 89 and once 89 is used not to go to 87. May seem trivial but just wondering...great site and thanks in advance guys!:)

jeep2011 11-27-2010 09:57 AM

Re: What Octane?
I always use what is recommended...its only around $2 more per fill up. I would use 87 if I had to.

topsailstar 11-27-2010 10:14 AM

Re: What Octane?
I use 87.

UNCjeepWK2 11-27-2010 10:23 AM

Re: What Octane?

plynn7 11-27-2010 10:28 AM

Re: What Octane?
I used 87 in my 08 Hemi, never had an issue in the the three years I had it.

ChrisWk 11-27-2010 10:33 AM

Re: What Octane?
I use both.

UNCjeepWK2 11-27-2010 10:37 AM

Re: What Octane?
I mean, I figure these people go to the trouble of engineering such a great engine, the least I can do is use the gas they recommend for it.

They didn't just flip a coin on which gas to use...

Red G8R 11-27-2010 10:49 AM

Re: What Octane?
I started with 89 for the Hemi during the first month. I've now gone to 87 and it feels fine. The following is taken from the Owner's Manual:

"This engine is designed to meet all emissions
regulations and provide satisfactory
fuel economy and performance when using
high-quality unleaded gasoline having
an octane range of 87 to 89.
The manufacturer recommends the use of 89 octane for
optimum performance. The use of premium gasoline is
not recommended, as it will not provide any benefit
over regular gasoline in these engines."

So,yes, 89 is recommended but 87 is acceptable. As I've mentioned in other threads, even Consumer Report say that if an octane is required then stick to that but if it's recommended, then you may use any octane.

2011JGC 11-27-2010 01:07 PM

Re: What Octane?
Why is 89 Octane recommended by Chrysler?

Dunecrawler 11-27-2010 02:08 PM

Re: What Octane?
FWIW, Only have 95 or 98 available here

Walt 11-27-2010 02:19 PM

Re: What Octane?

Originally Posted by 2011JGC (Post 307978)
Why is 89 Octane recommended by Chrysler?

Allows timing to be advanced without pinging or knocking. Theoretically, you can get more energy from the fuel charge.

I use 89 unless only 87 available when I tank up. Never noticed too significant a difference. Would recommend 89 if towing, long interstate trip, or in mountainous conditions.

DMack89 11-27-2010 02:31 PM

Re: What Octane?
Just bought my 05 jeep grand cherokee ltd 5.7 an use 93 octane... should I lower it a notch or two?

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