6.2 vs 5.3 and premium gas

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swathdiver

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Gotta admit, I read almost the entire thread. One question though - if we're all driving full size Chevy's (or GMC), do we really care about gas mileage THAT much? I mean seriously... If I was fuel conscious, I'd buy an electric truck or SUV. Rivian R1S is pretty fun to look at and explore. Not sure I'd own one, but it's a great start to a better environment. And it's not a Tesla.
For me, I've always viewed gas mileage as a way to determine the health of the drivetrain and suspension and to squeeze out the most power possible without compromising drivability.

100 Octane unleaded
Good stuff but bou cou bucks! There is a Sunoco nearby that used to sell 100 unleaded from the pump but the pump was not there the last time I drove by.
 

BG1988

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Gotta admit, I read almost the entire thread. One question though - if we're all driving full size Chevy's (or GMC), do we really care about gas mileage THAT much? I mean seriously... If I was fuel conscious, I'd buy an electric truck or SUV. Rivian R1S is pretty fun to look at and explore. Not sure I'd own one, but it's a great start to a better environment. And it's not a Tesla.
i bought for the safety factor rather then gas mileage....

the best I have done was 32mpg(mixed with v4 mode on) on the rig..

if i did some Aero mods i'm sure i could get it from the normal 19-21 to 32 around town and it would not even take many as plenty of low hanging fruit
 

ljn21

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I have years of experience with the 6.2 in my 2010 Sierra Denali I've owned for 11 years and six months. Noisy lifters at start-up, never tried 87 in it but a huge diff between 91 and 93 when I can find 93. Replaced OEM cast iron headers with Doug Thorley headers and less restrictive Magnaflow muffler in the first 3 months of ownership. Kind of senseless to do a Cat-Back since the General made the truck with 3 & 1/2 ", mandrel-bent exhaust and that really woke-up the 6.2 and added more low-end torque.

Our Daughter has a 2017 Caddy Escalade ESV that includes the 6.2 with over 88K on it and she surprised me by saying she ALWAYS runs 87 in it. Since she lives over 600 mi. away, I don't ride in it often but after a recent visit when I discovered the long-term 87 use, I started listening for any knocking or pinging and heard none....zero. Not sure what gives there....did the PCM re-calibrate itself over time and retard the timing or did Caddy do such a good job of insulating the firewall that pinging/knocking is unheard in the front seats ?

Recently bought a 2020 Yukon with the 5.3 to deliberately save $$ on the absurd extra-cost of Premium vs. the 6.2 and installed the GM cat-back system made by BORLA in search of fewer downshifts in our hilly terrain. THAT was money well-spent as there was an immediate improvement in power/torque and noticeably less or later downshifting when climbing the same hills....sounds pretty good too !

Any sounds clips of the exhaust and any comments on how it sounds when cruising along and the cylinders start kicking on/off? I really like the Corsa sound but considering the GM Perf exhaust as well. The GM exhaust sounds quieter than the Corsa but retains the valves which help with that potential drone when cruising.
 

jorgetoro

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I had a 6.2 2011 Camaro SS and went to the truck with 6.2. I like the 6.2, very good experiences. It sucks you are limited to premium gas but you kinda know that going into it.
 

PA-WOODCHUCK

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2016 XL and recently did 2 trips
1- 125 mile each way towing 6500lb boat&trailer on same road each way. Premium(93) fuel trip shows 13.9MPG and return trip with MID(89) reported 14.2mpg. NO difference noticed even on hills which peaked at 2400 elevation.

2- 500 mile round trip(not towing) going (87) w/10% 19.6mpg. Return (88 w/15%) 22mpg.

Gas door only recommends premium on label
 

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