Jump to content

Recommended Posts

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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    250.5k
    Total Topics
    2.7m
    Total Posts
  • Member Statistics

    342,947
    Total Members
    8,960
    Most Online
    Sothpaw27
    Newest Member
    Sothpaw27
    Joined
  • Who's Online   4 Members, 1 Anonymous, 549 Guests (See full list)

  • Latest Articles

  • Posts

    • Thanks - I wasn't quite caffeinated this morning. 2:1 makes sense, turning the crankshaft 360 degrees will turn the cam 180 degrees, and had I done that, the cam's dot would be at 6 and the crank's at 12 again.   I went ahead and took the sprocket off anyway, aligned everything dot-to-dot including the balance shaft just for s&g. I'm glad I did because I discovered no Loctite on the timing sprocket bolts. Maybe it's not required, but at only 20 ft-lb torque spec, those bolts aren't in there very tight. Cleaned and reassembled with some thread locker and torqued.   A general observation: Less is more with RTV. If a little doesn't stop a leak, a LOT probably won't, either. RTV is thinly veiled revenge, in a tube...      
    • The timing marks are ok, that is #1, you can turn it over until they line up and it won't change anything, the crankshaft turns twice for every camshaft revolution, I have always set up SB Chevs as your pic shows using a straight edge
    • Someone's been here before.... There is a receipt for a 3-piece timing set, purchased earlier this year.   Is this picture something, or, nothing?   I have the timing cover off and my crank is perfectly TDC and the keyed gear's locating mark is dead on 12 o'clock.   The cam gear locating mark is also at 12 o'clock. Now, I'm not an expert, but all the install guides say the two locating marks should meet and be perfectly aligned when installing a timing set. The mark on the crank should be dead on 12:00 and the cam gear's mark should be dead on 6:00, and both marks should be perfectly vertically aligned.   I believe the timing gear is keyed or has a dowel that ensures it can only be installed on the cam in one position, so I have to believe the cam is out of phase somehow. At the very least, with a triangular bolt pattern, it can only be installed in one of 3 different positions.   Before I pulled the front cover, the truck was running alright, no service engine soon lights except an occasional P0172 / rich condition. Timing -16 timing at idle (should be +16), and total -35% fuel trim, two conditions I haven't been able to figure out.   In related news, my injector tested pretty well, wasn't leaking, but I had it rebuilt anyway, and it's on it's way back to me.         Along with this discovery, the good and bad:   Good: The oil pan seal appears undamaged.   Bad: -The timing cover has been reused, and the positioning dowels have been broken. That could explain some of the leaking. -Some kind of white paste or grease was used to try to seal the oil pan seal and timing cover (since wiped off..). -Then, someone globbed silicone all over the front of the cover and also buried the ckp sensor in it. But, they didn't put any inside the cover or use RTV to try to seal the oil pan seal with the timing cover (good).
    • The guy that owns K&P filters last I checked in with him has over 300,000 miles on his Dodge base Hemi using his own 35 micron absolute stainless mesh filter from its first oil change.    The GM study I've posted a dozen times shows the relationship in engine life based in multiples of base units, not miles or years. That is the base unit is the number of miles the motor ran using the reference filter efficiency.    The above two paragraphs dismantle anecdotal arguments IF one changes oil often enough to prevent particle formation and the motor is in otherwise good shape. That is not full of silica (no air filter) or suffering a metallurgical issue that is not part of the lubrication discussion. Poor heat treat in example.   Data from UOA's I've reviewed from more than a few engines can show remarkably broad variations in oil cleanliness using the exact same filter over the course of an engines life.     Lastly there is the common sense of it. Wear debris WILL circulate the engine BEFORE it ever sees a filter in route to that filter and WILL harm the pump which NEVER sees filtered oil.    Alpha question then becomes, given the facts, how long do you believe is a reasonable service life from a vehicle you are certain you will not pass down? That is the junk yard will be it's resting place when you're done with it? (the moral issue most don't care about).    Omega question is then how diligent are you prepared to be in general mechanical, air & oil maintenance? Preventing particulates and keeping them sufficiently dilute; preventing the precursors from generation, amalgamation and precipitation.    If I get a good look at the engine bay of a vehicle I have a fair idea of the owners commitment to the inside of the power train. That 30 micron WIX is still more efficient than a sieve.                 
    • It also depends on what criteria someone is using for “best” when talking filters.  Are we going off best efficiency?   Best quality/QC?  Etc. because the two may not mutually exclusive.  
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...