Grade of oil

[the 18th letter]

I would not be surprised if some DEXOS 0W20 motor oils are better than others - they're not all identical.
Problem is oil manufacturers intentionally obfuscate.
How does one know if one DEXOS 0W20 motor oil is ACTUALLY better than another?NOT an error, it's intentional. If we were still changing oil every 3000 miles, engines would last too much longer.
Who really thinks GM wants all their engines to go 200,000 miles without any issues?Bet running the ATF hotter is worth 1 or 2MpG for the CAFE tests.
And again, a transmission that lasts 200,000 miles? Bad for GM's bottom line.0W30?
Which 0W30 comes closest to meeting DEXOS Gen3 standards?

I agree with this, that it's not complete incompetence:lol I'm not mechanically/engerirically inclined enough to justify a change in weight myself.

 

[the 18th letter]

running 5w-30 mobil 1 in my 6.2. no issues so far. 0w-20 was in it when it bent a pushrod couple months ago due to a lifter malfunction. ran 5w-30 in my 5.3 for the last 200k and it runs like a sowing machine with great oil pressure

what year is the 5.3? Does it have the AFM

 

[Mando6point2]

what year is the 5.3? Does it have the AFM

2010, unfortunately it doesnt have a DIC because its a low trim level but if my ear is right i think it does drop to 4 cylinders

 

[B-train]

I'm going to go against the grain and say use 5w-30 dexos. Ow-20 is only for CAFE certification so GM can make mpg marks (literally fractions of a mpg). The new 6.6L gas motor is identical architecture minus AFM/DFM and requires 5w-30. Anything meant for commercial use usually will get a beating over its lifetime, so I lean towards those specs vs. passenger car standards.

I personally have only rin 5w-30 in my 2017 and haven't had one issue. The oil stays clean for pretty much the whole 5k interval.

 

[the 18th letter]

I'm going to go against the grain and say use 5w-30 dexos. Ow-20 is only for CAFE certification so GM can make mpg marks (literally fractions of a mpg). The new 6.6L gas motor is identical architecture minus AFM/DFM and requires 5w-30. Anything meant for commercial use usually will get a beating over its lifetime, so I lean towards those specs vs. passenger car standards.

I personally have only rin 5w-30 in my 2017 and haven't had one issue. The oil stays clean for pretty much the whole 5k interval.

Is the AFM disabled on your rig? What type of miles have you run so far.

 

[Marky Dissod]

Is the AFM disabled on your rig? What type of miles have you run so far.

AFM / DFM is neither disabled nor enabled for the 6.6L L8T V8. The L8T has no such hardware or software.
It was designed - born - without any cylinder deactivation (although it still has VVT).

I'm going to go against the grain and say use 5W30 dexos.
OW20 is only for CAFE certification so GM can make mpg marks (literally fractions of a MpG).
The new 6.6L gas motor is identical architecture minus AFM/DFM and requires 5W30.
Anything meant for commercial use usually will get a beating over its lifetime, so I lean towards those specs vs. passenger car standards.

I personally have only rin 5w-30 in my 2017 and haven't had one issue.
The oil stays clean for pretty much the whole 5k interval.

Given every piece of data we LACK, this is one of the best educated guesses I've borne witness to in quite a long time.

 

[the 18th letter]

AFM / DFM is neither disabled nor enabled for the 6.6L L8T V8. The L8T has no such hardware or software.
It was designed - born - without any cylinder deactivation (although it still has VVT).Given every piece of data we LACK, this is one of the best educated guesses I've borne witness to in quite a long time.

Good looks, I read his post wrong.

 

[B-train]

AFM / DFM is neither disabled nor enabled for the 6.6L L8T V8. The L8T has no such hardware or software.
It was designed - born - without any cylinder deactivation (although it still has VVT).Given every piece of data we LACK, this is one of the best educated guesses I've borne witness to in quite a long time.

I don't have actual DATA to post to back this up.......just a number of years doing emissions and engine development testing. Then, many years of working on/using said products.

It's a simple game once you know the rules (hoops) to jump through for certifications. And, not one OEM cares about making it very far past the warranty stage, just their EPA credits and whatever it took to certify a powertrain - however dumb it may seem. Anything under the 8600 gvw falls into stupid land, over complex land, premature failure land, etc. Over 8600 gvw is EPA exempt from CAFE reporting/averaging. Hence all work trucks getting good engines with tunes intended to do ACTUAL WORK for the duration of the life.

Case in point: regular diesel truck gets more HP/TQ. Cab and Chassis (daily abuse) gets derated because it will get used hard for its entire life and needs to survive. Commercial sales are a big part of automaker sales - if they did AFM/DFM on work trucks and they failed at the rate they do in the working world, it would catch on quick and the OEM would lose TONS of business.

 

[Rygrego]

I would not be surprised if some DEXOS 0W20 motor oils are better than others - they're not all identical.
Problem is oil manufacturers intentionally obfuscate.
How does one know if one DEXOS 0W20 motor oil is ACTUALLY better than another?NOT an error, it's intentional. If we were still changing oil every 3000 miles, engines would last too much longer.
Who really thinks GM wants all their engines to go 200,000 miles without any issues?Bet running the ATF hotter is worth 1 or 2MpG for the CAFE tests.
And again, a transmission that lasts 200,000 miles? Bad for GM's bottom line.0W30?
Which 0W30 comes closest to meeting DEXOS Gen3 standards?

Any and all.

 

[mb1500]

AFM/DFM system is the very reason I stick to DexOS cert. 0W20. Give the most failure prone system the chance to operate under the conditions that it was designed.