I went from a 2021 6.2 to a 2023 3.0 LZ0 and I'm loving it.

JohnMr19 · August 5, 2023

My 2021 LTZ with the 6.2 (DFM) recently experienced the dreaded lifter failure at around 14,500 miles. I work out of state 2 out of 3 years, so I had to go to the local dealer in Wyoming. They did a good job getting to the truck within a week or so, but they only replaced one bank of lifters so I decided to cut my losses and trade. My dealer back home in Montana had a 2023 HC with the LZ0 (I had been reading a lot of good reviews about its predessesor the LM2) so I decided to give it a shot. So far I am very pleased with the truck and quite impressed with the diesel engine. Once I got used to the throttle response, I found the engine has plenty of power for me and the torque is impressive. I've made a couple of trips between Montana and Wyoming averaging 28 mpg while driving between 75 and 85. My best mileage was 31 mpg taking a trip to the golf course in Nebraska (60 miles). Around town gets me between 24 and 29 depending on stop and go conditions. I haven't pulled my cargo trailer yet, but I imagine from what I've read here, it will do very well. I have about 4,500 miles on the truck now and have only had to put DEF in twice (was only down half-way each time). I've tried to figure out when it's doing a regen, but only once or twice I thought it may be because of the smell. This is my first diesel and I was a little nervous about it, but it has been pretty effortless. Not having to worry about lifter failure is a big bonus, plus I really like the refresh interior.

Edited August 5, 2023 by JohnMr19

BigMick2023 · August 5, 2023

Good on you......the refreshed interior is definitely very nice, I love my 2023 High Country also.

Diesel wouldn't work for me, but for your use it sounds like a good fit.

I have the 5.3 and no worries here......just enjoying the truck big time.

Jus Cruisin · August 5, 2023

Nice. I'm just over dealing with diesels. That's just me. I have a marina boat neighbor that has had the baby Duramax for over 2 years and still is thrilled with it.

seamus2154 · August 9, 2023

I have had several 6.2 and its a rocket ship. Loved that motor. Bought a 2021 denali with 3.0. Literally the best truck i have ever owned and the fuel mileage is fantastic. Tows like a boss. 2 days ago we went to the local dealer who had a perfect 1 owner, garage kept, maintained Yukon denali. Had the 6.2 motor and its for the wife so i was considering it. Very well versed with the lifter issue since 2020. It had 33k on it and was showroom new. Then read the Carfax a bit more carefully and saw the lifters had been replaced at 21K!!!!! I came to my senses and I will never consider signing up for that possiblity at the price point especially. 3.0 or nothing.

Bikerjon · August 9, 2023

Nice lookng truck!

Moyses · August 11, 2023

I went to my dealer this week to order one. I drove the 6.2 and 3.0 diesel. I confess that I was tempted by diesel because of its good performance and excellent fuel economy. But still have that little doubt which one to buy. I'm ordering an Ultimate but I don't know if I'm going for 6.2 or 3.0.

repairman54 · August 11, 2023

Emissions diesel and the oil pump belt are a major turn off for me on the 3.0

Jus Cruisin · August 11, 2023

12 hours ago, Moyses said:

I went to my dealer this week to order one. I drove the 6.2 and 3.0 diesel. I confess that I was tempted by diesel because of its good performance and excellent fuel economy. But still have that little doubt which one to buy. I'm ordering an Ultimate but I don't know if I'm going for 6.2 or 3.0.

I have a 6.2l Ultimate. You can get pretty good mpg's with it. This was a 14 mile run from Colony Marine in St Clair Shores to my marina in Harrison Township. Took surface streets all the way with some stop and go. This was as I was pulling into the marina. I do all short trips as everything I need is close by. And overall mpg is 16.

Edited August 11, 2023 by Jus Cruisin

Moyses · August 11, 2023

Very good. It really is the hardest part of the decision. As for the truck, there's no mistake. One of the best I've ever had, if not the best by far.

JohnMr19 · November 16, 2023

Update: I have almost 10,000 miles on the truck now and am still very happy with it. I'm getting anywhere from 28 to 32 MPG around town depending on stop and go conditions. Still getting 28 MPG on average on the highway, but wind is always a factor in Montana/Wyoming (I believe cold temps also affect mileage as well). DEF usage is quite mild around town - I went roughly 500 miles over a month around town before the DEF guage dropped a notch. Getting around 2,500 miles per DEF tank roughly on the highway. Still haven't towed yet, but that time is approaching when I move in December and pull my 7x14 cargo trailer with household goods (roughly 5,000 lbs). It will be interesting to see the actual mileage and DEF usage then. I'll keep eveyone posted. Truck rides like a dream and the diesel engine has good throttle response unless you're trying to drag race - low end torque is quite refreshing.

The only issues I've had with the truck itself is a failed OTA update I had to get the code reset on and now I have a collision avoidance light on the cluster. I parked the other day and got close enough to the vehicle in front of me to make the park assist vibrate and then the light came on. I have an appointment after Thanksgiving to get it checked - I imagine they'll just have to reset that code as well (hopefully). Overall I'm extremely happy with my purchase.

redwngr · November 16, 2023

First time I added DEF was at 7315 miles.

Worked out to 1481 USMPG

I record every fuel fill, and compare DIC tripmeter mileage with hand calc mileage.

Hand calc lifetime average is currently 29.1 mpg

SVG · November 16, 2023

14 hours ago, JohnMr19 said:

Still haven't towed yet, but that time is approaching when I move in December and pull my 7x14 cargo trailer with household goods (roughly 5,000 lbs). It will be interesting to see the actual mileage and DEF usage then. I'll keep everyone posted.

When I tow my 5K lb boat/trailer my DEF consumption goes way up. Power has never been an issue.

Depending on how far your move is it might not be a bad idea to throw a box of DEF in the bed just in case.

(I have a LM2, not a LZ0)

JohnMr19 · November 18, 2023

On 11/16/2023 at 10:20 AM, SVG said:

When I tow my 5K lb boat/trailer my DEF consumption goes way up. Power has never been an issue.

Depending on how far your move is it might not be a bad idea to throw a box of DEF in the bed just in case.

It's roughly 670 miles from Cheyenne to Great Falls. There are many stations along the way with DEF pumps, but I'll definitley have a box on board just in case.

JohnMr19 · November 18, 2023

On 11/15/2023 at 11:05 PM, redwngr said:

First time I added DEF was at 7315 miles.

Worked out to 1481 USMPG

I record every fuel fill, and compare DIC tripmeter mileage with hand calc mileage.

Hand calc lifetime average is currently 29.1 mpg

That's amazing DEF mileage! I thought 2500 miles/tank was good. Looks like my fuel mileage is pretty similar depending on driving and weather conditions.

PowDuck · November 23, 2023

10,000 miles on my ‘23 model and loving the diesel. My total mpg so far is 25.2

I’ve gotten as high as 33.8 on two lane trips.
My DEF runs about a gallon every 1000 miles.
I’ve done some towing (28’ camper and 12’ utility) and the truck behaves very well with impressive power and mileage.
On a recent 3700 mile round trip to central Saskatchewan it got 25.2 and used a touch over 1/2 tank of DEF. I see no reason to ever carry a box of DEF with me as long as there are trucks on the road there will be truck stops with DEF pumps.

My last truck was an ‘07 Dodge with the 5.9l Cummins so I know towing power.

Edited November 23, 2023 by PowDuck