6.2L or Duramax reliability

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DuraYuk

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Let me bring it back with some more fun.

I just got a 6.2, and the dealer said I don't need premium, but everything I have read and seen says I need to use 93 gas if possible. We have it all over here so I would.

To be honest I am going to do it no matter what as I don't like using lower grade fuels regardless. But why would the dealer tell me no and don't worry about it?

I like them, trust them and they were a low pressure easy sale. So I was confused when he told me I didn't need to do it, or even really suggest I do.
owners manual says premium recommended for max performance....not premium required. http://car-owners-manual.com/chevro...nd-operating/recommended-fuel-6-2l-v8-engine/

As for premium gas vs low tier it's just the anti knock agents that are different. I wouldn't say the gas is better quality. So if a car requires it it's necessary so it doesn't knock (high compression motors etc).
 
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NothEastTahoe

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owners manual says premium recommended for max performance....not premium required. http://car-owners-manual.com/chevro...nd-operating/recommended-fuel-6-2l-v8-engine/

As for premium gas vs low tier it's just the anti knock agents that are different. I wouldn't say the gas is better quality. So if a car requires it it's necessary so it doesn't knock (high compression motors etc).
Thanks for differentiating between with knock agent link. And obviously I am in it for max performance!
 

TollKeeper

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I have to admit, I didnt know it was a wet belt! Ford has not been having very good luck with them, so why would GM have any better luck?
 

Polo08816

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I have to admit, I didnt know it was a wet belt! Ford has not been having very good luck with them, so why would GM have any better luck?

You're referring to the belts on the 5.0 Coyote? I think the 3.5EBs have timing chains. Although both of their designs have the belt/chain on the front of the engine instead of behind.

150,000-200,000 service interval is not bad though - you likely only have to do it once at most for the life of the vehicle.
 

WalleyeMikeIII

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Again, blah blah blah ... Why do you need all the power of the engine?) to tear the trailer apart?))) You lose the thread of the conversation, you are constantly trying to take it aside. About miles per gallon, I showed you clearly that I can easily get the same figures at 6,2 ..you have only words and words all the time .. No photos or evidence)))
Dura Yuk is correct about this one...as it relates to torque.

To tow you need torque, esp when going uphill. Diesels are at max torque at the low range of their RPM's, for a gasser, you usually have to get up in the RPM's to get the max torque...so, in those cases, the automakers usually tune the shift points in the transmission controls accordingly.

Suggest doing a YouTube search for TLF Truck "IKE Gauntlet"

Those guys tow at max load up a very steep mountain grade, and do it with most all of the powertrains available in most brands of trucks.
They tested both the 3.0 Duramax and the 6.2L in both GM Pickups and in the SUV (not sure if they did the duramax in the Suburban/Yukon) or not. They measure MPG, engine braking, noise, the whole gamut....it is very enlightening.

Diesel will almost always win in a towing competition, and a fuel economy competition; because the characteristics of the engine deliver peak torque sooner, and because diesel fuel has a higher energy density than gas.

The gas engine will put way more smiles on your face if what you like is acceleration. Both have their purpose...and it is personal preference and application as to which works best for a given user. This is why GM offered a choice in the powertrain.

I drag my 4500lb boat trailer all over the place (before was w/ a 5.3L in my 2013 suburban, usually to the tune of 12-13MPG, and now w/ my 6.2L Denali, usually to the tune of about 16MPG) we have hills and such around here, and some interstates I drive on w/ the boat I need to be at 70-71MPH to not get blown off the road by other traffic. I suspect the 3.0 duramax would do a little better than the 16MPG, and know it would be great when not towing...I chose the gas for the fun factor...and I am not disappointed. If my lifters blow out my valvetrain, I'm blessed becuase my dealer "included" a lifetime powertrain warranty...so aside from some downtime, I'll be whole in the pocketbook.
 
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Polo08816

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Dura Yuk is correct about this one...as it relates to torque.

To tow you need torque, esp when going uphill. Diesels are at max torque at the low range of their RPM's, for a gasser, you usually have to get up in the RPM's to get the max torque...so, in those cases, the automakers usually tune the shift points in the transmission controls accordingly.

Suggest doing a YouTube search for TLF Truck "IKE Gauntlet"

Those guys tow at max load up a very steep mountain grade, and do it with most all of the powertrains available in most brands of trucks.
They tested both the 3.0 Duramax and the 6.2L in both GM Pickups and in the SUV (not sure if they did the duramax in the Suburban/Yukon) or not. They measure MPG, engine braking, noise, the whole gamut....it is very enlightening.

Diesel will almost always win in a towing competition, and a fuel economy competition; because the characteristics of the engine deliver peak torque sooner, and because diesel fuel has a higher energy density than gas.

The gas engine will put way more smiles on your face if what you like is acceleration. Both have their purpose...and it is personal preference and application as to which works best for a given user. This is why GM offered a choice in the powertrain.

I drag my 4500lb boat trailer all over the place (before was w/ a 5.3L in my 2013 suburban, usually to the tune of 12-13MPG, and now w/ my 6.2L Denali, usually to the tune of about 16MPG) we have hills and such around here, and some interstates I drive on w/ the boat I need to be at 70-71MPH to not get blown off the road by other traffic. I suspect the 3.0 duramax would do a little better than the 16MPG, and know it would be great when not towing...I chose the gas for the fun factor...and I am not disappointed. If my lifters blow out my valvetrain, I'm blessed becuase my dealer "included" a lifetime powertrain warranty...so aside from some downtime, I'll be whole in the pocketbook.

The 2 reasons why diesel powertrains are preferred for towing heavy are 1. fuel economy and 2. exhaust braking capabilities for going down grades.

You don't need "torque" to tow and go uphill - you need power. However, engines that tend to be more fuel efficient in a towing application tend to have high torque because of the frictional losses at high RPM.

Automakers could theoretically develop a big block NA V8 to provide as much or more power than a diesel like the L5P Gen 2. The problem is that for applications that need that amount of power also need the exhaust braking capabilities for slowing that load down.
 

WalleyeMikeIII

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The 2 reasons why diesel powertrains are preferred for towing heavy are 1. fuel economy and 2. exhaust braking capabilities for going down grades.

You don't need "torque" to tow and go uphill - you need power. However, engines that tend to be more fuel efficient in a towing application tend to have high torque because of the frictional losses at high RPM.

Automakers could theoretically develop a big block NA V8 to provide as much or more power than a diesel like the L5P Gen 2. The problem is that for applications that need that amount of power also need the exhaust braking capabilities for slowing that load down.
That makes good sense! Note, the TFL guys did note that the exhaust braking on the 3.0 Duramax is not nearly as good as on the bigger ones (makes total sense).
 

Polo08816

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That makes good sense! Note, the TFL guys did note that the exhaust braking on the 3.0 Duramax is not nearly as good as on the bigger ones (makes total sense).

So the Youtube Channel - TheGettyAdventures - made a good video why the LM2 and LZ0 are much better than their Stellantis and Ford counterparts:



They were designed with emissions requirements in mind versus the other diesel powertrains that had to add emissions components afterwards.
 

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