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Posted

Hey All,

 

Just traded in my 5.3 for a 6.2.  I've always used Race Trac/Wawa (87 octane in the 5.3), as they are closest to the house/work.  Question is, for the 6.2, would you go with 93 octane at Race Trac/Wawa for $3.55 (current price) or 91 octane at Costco for $3.05 (current price).  Just curious if the extra $10-$12 per tank is necessary for 93 over 91.  I have a Costco closeish to the house and another on the way home from work.  Not completely ideal, but also not out of the way.  I have no problem spending the extra ~$500 over the course of the year if needed to keep the engine in optimal running condition.  Also, I don't want to get in an octane pissing match, just looking for feedback.

 

Thanks,

Posted

If you read the user manual, it recommends 93 octane for peak performance and states 87 octane is fine. I had a 2019 6.2l and only ran 87 octane with no issues (recently upgraded to a 2500). Car and drive had an article back in 2016 I believe where they did dyno runs on a escalade with a 6.2l with both 87 and 93. With 87 it lost ~20hp is what they found. So if you are okay with a little power loss, you should be fine.

 

So basically both 87 and 93 are safe, but your engine is changing timings while running 87 resulting in power loss

Posted
4 hours ago, vancealot29 said:

Hey All,

 

Just traded in my 5.3 for a 6.2.  I've always used Race Trac/Wawa (87 octane in the 5.3), as they are closest to the house/work.  Question is, for the 6.2, would you go with 93 octane at Race Trac/Wawa for $3.55 (current price) or 91 octane at Costco for $3.05 (current price).  Just curious if the extra $10-$12 per tank is necessary for 93 over 91.  I have a Costco closeish to the house and another on the way home from work.  Not completely ideal, but also not out of the way.  I have no problem spending the extra ~$500 over the course of the year if needed to keep the engine in optimal running condition.  Also, I don't want to get in an octane pissing match, just looking for feedback.

 

Thanks,

I would add here that you should use Top Tier gas.  I didn't check to see if the stations you mentioned are top tier certified, but that gas has more detergents to keep your engine running better and longer.  

 

On the topic of octane, if you experience knocking then you can try running 89 vs 87.  Or, whatever the mid-grade fuel type is in your location.  Another option is using 87 then adding fuel additives to bring up the octane and/or detergents.

  • Like 1
Posted

I purchased the 6.2 for the performance so I run 93.  If you can afford it and it isn't an issue then go that route.  If money is tight then go the WaWa route. In the end you need to be happy.

  • Like 2
Posted

If the costco stuff is that much cheaper, just run that. Some people are so picky about 93 octane and top tier bologna. I have never once went to a gas station and wondered if they used top tier fuels and never had a problem with how my vehicles run.

 

If you can feel a difference that isn't just in your head between 91 and 93 octane you must be super duper special.

  • Like 1
Posted (edited)

Costco is top tier. If GM recommends 93 and says 87 in fine. I think for the price the Costco 91 should be good. 

 

I wouldn't have got the 6.2. I don't have/ want to spend the extra money on the motor and fuel. But if I did buy the 6.2 I would run 93 to get the full potential of the motor.

Edited by Adamace1
  • Like 1
Posted

I get that people want the full potential but when 99% of your driving is at steady speed, idling, in traffic and not 100% throttle, can your really feel that 5-10hp difference??

 

I'll end my rant now. I've tuned plenty of cars/trucks to know that it doesn't make a big enough difference unless in some extreme conditions.

  • Like 1
Posted

What elevation are you driving?  You will find that lower elevations closer to sea level will offer 93.  I'm in the PHX area 1300+ average and there is no 93, only 91.  Basically the thicker the air (lower elevations), the higher octane you need to make highest power.  Close to sea level, 93 will give highest power for the 6.2, if you run 1k feet elevation and higher, 91 is fine.  If you are up in the mountains 5k+, you are probably fine with 89 to 87.

Posted
1 hour ago, MG386 said:

What elevation are you driving?  You will find that lower elevations closer to sea level will offer 93.  I'm in the PHX area 1300+ average and there is no 93, only 91.  Basically the thicker the air (lower elevations), the higher octane you need to make highest power.  Close to sea level, 93 will give highest power for the 6.2, if you run 1k feet elevation and higher, 91 is fine.  If you are up in the mountains 5k+, you are probably fine with 89 to 87.

I'm at sea level and all premium at every station is 90 octane.  No such thing as 91 octane or higher anywhere in the state.  Regular is 87 and midgrade is 88.5.

Posted
1 hour ago, MG386 said:

What elevation are you driving? 

FL peninsula for 95%+ of my driving. Never more than 150 ft. above sea level, probably usually closer to 50 ft.

 

I agree with most that 91 will suffice, but I will probably still stick with the 93 for piece of mind.

  • Like 1

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