Are you still using premium gas?

[pokismoki]

20 hours ago, Wiggums said:

 

My mechanic said to use that if I don't refuel in over six months. For now, it's been three months when I refuel so.. no need.

use techron, its has stabilizer built into the stuff

[BIGDOGx]

I dont get why someone would pay 60+ grand for the lux truck model and then save 5-10 bucks a fill up to put lesser grade dirtier fuel into their engines which the manufacture clearly doesn't recommend. Have any of you seen a person who has taken the top half of one of these di motors apart because the valve caking is an absolute real issue everyone with one of these engines will face, using cheaper fuel will only make the issue worse.

 

If your a pump and dumper and trade out like you do socks then it most likely will never be an issue for you, the person who buys it will be a different issue.

[KARNUT]

I can see with not only gas going up trying to save some money on gas using regular or mid grade. I imagine with the money used trucks are bringing currently if things don’t change soon. If people cringe fueling up it will be traded in.

[Grumpy Bear]

On 6/12/2022 at 12:25 PM, zelmo said:

Recommended Fuel (6.2L
V8 Engine)

Premium unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 93 —
(R+M)/2 — is highly recommended
for best performance and fuel
economy. Unleaded gasoline with
an octane rated as low as 87 can be
used. Using unleaded gasoline
rated below 93 octane, however, will
lead to reduced acceleration and
fuel economy. If knocking occurs,
use a gasoline rated at 93 octane
as soon as possible, otherwise, the
engine could be damaged. If heavy
knocking is heard when using
gasoline with a 93 octane rating, the
engine needs service.

 

Peace offering if I may....

 

Fine point here worth its distinction. The "knock' the sensor detects and corrects for is what is called incipient detonation. It is NOT audible to the average human ear but it is detectable to the sensor. It can run in this condition forever without damaging a thing. LV3 motors eats it like popcorn.

 

The detonation referred to in the manual above is AUDIBLE detonation. Not the little click clack of the HPFP but an audible metallic rattle or "PING" that is unmistakable from any other sound the motor may make. You won't need a scanner to know your motor is suffering. That one tears things up fast. It can also be controlled with the loud pedal and gear selection (load) which will be required until you get enough space in that tank for 93 to make a real difference. Octane is a blend-able number. Straight up ratio and proportion.

 

Arguments in this matter are often the result of confusing one type for the other. This is sometimes augmented by the fact that so many younger people have never experienced true audible detonation as the KIR systems in the cars they learned to drive in worked so well. 

 

Enjoy the ride  

[swathdiver]

1 hour ago, Gangly said:

If you have no knock running E85, then why don't you run it year round, every tank?  I guess some knock is acceptable, or is it that you don't want to pay so much?  Which is it, because either answer will contradict your opinions on the matter?

 

No knock on E85 all through the rpm range, some knock on 93 at WOT.  I run 93 when the convenience of range is needed and don't want to be looking around for ethanol pumps when out of town.  WOT knock on 93 is minimal, have recorded it to show you guys but don't know how to post it.  Someday I'll corral one of the kids to get it done.

 

6.2 DI motors are 11.5:1.  

[Grumpy Bear]

3 minutes ago, swathdiver said:

 

No knock on E85 all through the rpm range, some knock on 93 at WOT.  I run 93 when the convenience of range is needed and don't want to be looking around for ethanol pumps when out of town.  WOT knock on 93 is minimal, have recorded it to show you guys but don't know how to post it.  Someday I'll corral one of the kids to get it done.

 

6.2 DI motors are 11.5:1.  

 

No audible knock in my LV3 with any fuel but incipient is as you describe for the 6.2 to the "T" as read by the scan tool. She is still pulling timing running 93!  But never on E40 or greater ethanol blends.  But until recently has lived pretty much on 87 for her entire life to date. 155K. 

 

LV1 and LV3 are 11.0 : 1 CR

[swathdiver]

11 minutes ago, Grumpy Bear said:

 

No audible knock in my LV3 with any fuel but incipient is as you describe for the 6.2 to the "T" as read by the scan tool. She is still pulling timing running 93!  But never on E40 or greater ethanol blends.  But until recently has lived pretty much on 87 for her entire life to date. 155K. 

 

LV1 and LV3 are 11.0 : 1 CR

I didn't do a good job of explaining the differences as you have in these two posts.  There is indeed a difference and these new DI motors are less affected by octane than the older motors.

[JimCost2014]

but don't grab a pitchfork and start talking high and mighty

 

Sooooo, for us memebers in the 92+ octane club, what should we use now

[Grumpy Bear]

2 hours ago, swathdiver said:

I didn't do a good job of explaining the differences as you have in these two posts.  There is indeed a difference and these new DI motors are less affected by octane than the older motors.

 

I knew what you meant  I'm old...

[f8l vnm]

ever since i got my 2019 6.2 i have been like 70/30 using 91 and sometimes 87 .  

I never tow but once a week haul a big load 2k . my truck has never pinged , never had any issues on 87 but i also drive fairly normal. I do sometimes get on and the 6.2 roars . 

If your not towing heavy loads, or not up in altitude a lot and not racing light to light . 87 does just fine. 

For max performance , yes the higher octane does little better.   

[TNTSierra]

Premium was $1 more today. I still choose premium because I bought a damn 6.2L for “the power”.  

I also read an article that came out yesterday about the high cases of defaulting auto loans.  So many “fools” over budgeted themselves during the pandemic because they had the government money coming in, interest rates were low, and they WANTED something new.  Not thinking about the consequences of what the future holds.  Well it’s going to get worse before it gets better. I just pray we as a society can get through it without more chaos!!

[shakenfake]

Still using premium. Have considered e85 conversion but I got other stuff to do. $5.30 last time I checked

 

Edit: 14.5 mpg was my last few fillups. I have a weird feeling something is going on since that is a major drop in the past couple months

Edited June 16, 2022 by shakenfake

[Black02Silverado]

We just took a trip in our 2016 Suburban with the 5.3 and I installed the ethanol sensor,  Black Bear Performance tuned it and turned on the E85 table and I imagine tuned that as well, or tweaked it.  I ran E85 the entire trip and put around 1,200 miles on it.  We averaged 17mpg when normally would get 21mpg on 93.  The difference is that E85 where I got it was and is that I know of $3.70 and 93 is $4.90 to $5.60 in places in PA.  Our cost per mile was break even for the most part but I didn't do the math 100%.  I just like the performance of E85 and the smell of the exhaust.  Not to mention the benefits of it burning cleaner.  My UOA's prove that.

 

As for my 6.2, I use 93 and when I can mix E85 along with it.  I found anything more than a 40/60 mix throws a CEL for running lean code P0171

 

GM and all the other manufactures should just make every ICE vehicle a flex fuel and let us decide if we want to us it or not.  I know it isn't available everywhere. 

[TxTruckMan]

If you can't afford the premium gas, you shouldn't be driving a truck with a premium engine.  Sell it and buy a Prius.

[KARNUT]

15 minutes ago, TxTruckMan said:

If you can't afford the premium gas, you shouldn't be driving a truck with a premium engine.  Sell it and buy a Prius.

I hear you if you said that a year ago. Sure we were warned that the current administration is anti oil. In case you haven’t noticed it’s doubled along with just about everything else. So that statement today doesn’t hold up. I personally use my truck as personal pleasure vehicle and can adjust my usage. When the prices drop on the mighty 6.2 or a 5.0 and maybe a hemi 2 door I may scoop one up. I’m starting to see 10K off plus discounted interest rates already. I’m starting to see some housing slow downs. Struggling to buy premium gas, that’s just the tip of the iceberg.