GAS 87, 89 or 91?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

dpak

New Member
Joined
Aug 25, 2007
Messages
9
Reaction score
0
This has probably been asked before but I couldnt not find it..

What grade gas do you all put in?

I have been filling up on 89 but if its not necessary then maybe i'll just do 87? And does it make any difference? Thanks!
 

boblasek

New Member
Joined
Aug 17, 2007
Messages
2
Reaction score
0
I believe the manual says 87, but 89 should be fine as well. THe only reason you would go higher octane is if you have a high compression engine (please correct meif i am wrong) because it prevents detonation or pinging
 

Getwired

Full Access Member
Joined
Jul 24, 2007
Messages
1,591
Reaction score
0
Location
DC Suburbs
93 in my 07 Yukon Denali

The 6.2 really doesn't like the 87 as much as the 93. I get minor knocking/pinging after a couple tanks full, and there is definitely less power. I ran through some Shell V-Power (2 tanks worth) and things are now running great on the conventional 93 octane stuff I can pump for a lot less @ Costco (difference is a lot less detergents and stuff vs. V-Power). I guess I'll run a tank or two of V-Power every few months just to keep things good and clean.

Main difference with 93 over 87: better performance, better mileage. I used to be @ 9.9 MPG on 87 (mixed driving) prior to my intake and Mobil1, and now I'm at around 12 MPG and change (same mixed driving) if I keep my foot out of it. 93 is about 6% more costly than 87 for me , and it seems to provide at least 10% better mileage (not including the boost from Mobil1 and the Volant intake). I'm interested to see what the Edge Evolution programmer can do on the economy tune as well. [I'm planning on running premium fuel in this thing all the time.]
 

TimCinNWOR

New Member
Joined
Jul 17, 2007
Messages
6
Reaction score
0
It depends. Generally, you will get better performance and gas mileage with higher octane depending on how you drive.

If you know what your mileage is when you use 87 octane, then switch to using 89 octane for awhile and then calculate your mileage. 89 is usually 10 cents more per gallon or $2.00 per 20 gallon fillup.

$2.00 would buy you less than one gallon of 87 octane, which would take you roughly 10-12 miles.

If your gas mileage improves by 1 mpg when you switched to 89 octane, then you be going 20 miles farther on a tank of 89.

Lots of generalizations there, but that's how you can figure out if switching to 89 would save some money. Your mileage may vary. :lol:

Now that I re-read your question, the same ideas apply, except that you would probably notice a drop in mileage by switching to 87.

We use 87 in our 03 Tahoe with the 5.3L. I'm thinking we should use 89 when we tow our trailer though.
 

dpak

New Member
Joined
Aug 25, 2007
Messages
9
Reaction score
0
I see. Thank you for the thorough response.

I have the 4.8L engine. I'll try with 87 to see if i see any difference next fillup.

=)
 
Top