6.2L or Duramax reliability

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steiny93

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I dump in a 2.5 appx every 10K miles from Wally World. About 10 bucks... a total non issue.... And a great oil change container!
You get 10k miles out of a 2.5 gallon container of def?
Really? Are you sure?

We have 5 of the baby dmax's in a group here at work and all of use get around 1k miles per gallon of def when empty. Towing they use significantly more (8.2 gallons during my last 1500 mile trip pulling 5k lbs).

GM also states the 1k per gallon number as an estimate.
 

StephenPT

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You get 10k miles out of a 2.5 gallon container of def?
Really? Are you sure?

We have 5 of the baby dmax's in a group here at work and all of use get around 1k miles per gallon of def when empty. Towing they use significantly more (8.2 gallons during my last 1500 mile trip pulling 5k lbs).

GM also states the 1k per gallon number as an estimate.
Must've been a typo. I'm about to add my second 2.5G jug and just hit 7K on mine. Five gallons in 7K miles seems to be very reasonable usage and inline with many other owners of the LM2. Also, I have not done any towing up to this point.
 

Pro299

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You get 10k miles out of a 2.5 gallon container of def?
Really? Are you sure?

We have 5 of the baby dmax's in a group here at work and all of use get around 1k miles per gallon of def when empty. Towing they use significantly more (8.2 gallons during my last 1500 mile trip pulling 5k lbs).

GM also states the 1k per gallon number as an estimate.
I've yet to put in more than one 2.5 gallon jug of DEF between oil changes at 5K. I do not tow with the Yukon, however, so my experience is to just pick up a jug after an oil change and when it's down to 1/2 on the gage I pour it in.
 

steiny93

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I've yet to put in more than one 2.5 gallon jug of DEF between oil changes at 5K. I do not tow with the Yukon, however, so my experience is to just pick up a jug after an oil change and when it's down to 1/2 on the gage I pour it in.
wow; you are using significantly less def then what we are seeing

[no towing; empty only] If the def tank is full; following the oil change ticker (I believe this is 7500 miles) on the dash, it will consume the def tank and nearly be empty again after putting in a 2.5 gallon jug.

right now; my biggest complaint on the baby dmax is the size of the def tank; they should triple it
 

Seamus

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I've yet to put in more than one 2.5 gallon jug of DEF between oil changes at 5K. I do not tow with the Yukon, however, so my experience is to just pick up a jug after an oil change and when it's down to 1/2 on the gage I pour it in.
I am about the same. I use very little DEF under normal driving. I bought 10- 2.5 jugs a year ago and never need DEF. It goes to half right around my 5K oil change. Towing I use plenty. 1-2 jugs in 1600 miles of towing to Va.. I am doing about 12K a year and adding DEF 1-3 times of a 2.5 gallon jug.
 

xycrazy

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I own the 6.2L and I’m quite happy with it. Did a trip to Canada. 1,500 miles in 5 days. I averaged 19.3mpg. No problems whatsoever. I’m at 35k miles right now and it’s the 2021.

That being said, I would go for the 5.3L next time. Plenty of power and significantly better gas mileage (got around 20.8 mpg on a 500 mile road trip in a 2021 rental Yukon)

The 6.2L is not worth the extra money in my opinion. The 5.3L with the 10 speed automatic in the 2021+ models is a totally different beast than in the old model. I know what I’m talking about since I had it in my previous 2017 Yukon and it was night and day.

Go with the Duramax if you can get it or take the 5.3L if you don’t want to get annoyed with DEF fill ups
 

WalleyeMikeIII

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The 6.2L is not worth the extra money in my opinion. The 5.3L with the 10 speed automatic in the 2021+ models is a totally different beast than in the old model. I know what I’m talking about since I had it in my previous 2017 Yukon and it was night and day.
It is (over the 5.3) if you tow! The 3.0 comes at a Discount to the 6.2 in the Denali...so...if you are looking at that trim, its a no brainer to go w/ it if Fuel Economy is your goal.

Incidentally, over a 750 mile set of road trips over 3-days, I averaged 21.6 in my Denali (6.2), but it was all 2 lane roads, didn't really exceed 65 MPH the whole time, no wind.
 
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Hey Raj welcome to the fun / forum.

I’ve had **two** 2023 Yukon Denali’s now, yes read that correctly. Our first was with the 6.2 L and the motor was blown after less than 4000 miles. Our second replacement 6.2 L Yukon also 2023 Denali has just over 4000 miles right now and everything is going well.

I saw someone mention that the 6.2 L makes the truck somewhat of a hot rod. Funny comment but couldn’t agree more. I had the option to replace with the Duramax but I didn’t want to give up the rumble of the 6.2 L V8. I also went with the cat back performance exhaust system, and it really sounds pretty awesome. I’m in Southern California and most of my trips are usually at least one hour, so I am definitely sacrificing for the gas mileage I would have had with the Duramax motor. That said I couldn’t be happier although I haven’t checked my bank account in a while, I think last month we spent about $800 on gas. Mind you, that included 2 Vegas trips . Good luck with your decision. My advice is get whatever makes you happy. You’re spending $90k either way.
 
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raj07

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Thanks a lot for all the advice. I have boiled it down to two options. Denali XL with 6.2L, I'm ok spending some more on fuel plus the vehicle will be exclusively for road trips. Second option - practicality - well optioned SLT with Duramax. The second is hard to find. I think I will end up with the first one - heart vs mind..high power and rumble and all !
 

Hotrod61483

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I'm surprised there's not more people Rallying with the 6.2L. IMO the 6.2L is hard to beat in reliability and performance, I've owned several and they have proven themselves to me. I drive a 2015 Yukon Denali XL and it's the same Echotec 3 engine from 2015-2020. I can't attest to a brand new one, nor do I know about any issues the newer one's have had. That being said I have heard of a lot of the 6.2L engines with the notorious GM Lifter Tick. Luckily mine hasn't started ticking yet, but my 2010 Yukon Denali XL was plagued with a slight lifter tick. It didn't really affect the reliability of it, it's still capable of 300+ thousand miles even with a slight tick. This is just me, but if I had the choice between the 5.3L, the 6.2L, or the Baby Duramax I would choose the 6.2L hands down.
 

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