LZ0 Duramax Decision - Input Requested

[BobbySC]

Just did 450 with mine... still 1/4 tank left. All I need to know....

Yup. I’ve got over 600 on a tank.

Last car tank was 5 gallons smaller, got 300 if lucky and took premium.

 

[Eighthtry]

The air ride suspension is definitely worth it. Just make sure when you take it in for alignment you tell the service manager, the service representative, and the janitor to read the owners manual prior to doing it. Your tires might last another 1,000 miles otherwise.

No question in my mind on the 6.2. If you expect to run it 200,000+ miles, which is very realistic.

I hate turbos. They are a definite wear part on a high mileage truck. At 200,000 miles you can expect to have replaced it twice, if not more. If you are thinking a service life of 75,000 miles then it likely does not matter.

You do not need catch cans or anything else. Somehow I have managed to coax 200,000 to 300,000 miles out of gas 6.2's and 5.3's with no, as in none, problems. No oil consumption ever. GM would have added catch cans, dual filtration, or whatever to their diesel lines if they needed it.

I buy the GM Extended Warranties. Funny how I have never use it but once on my other high mileage applications. And it was not the engine.

The 10 speed will likely be entertaining. Yours will either work or it will break. Hard to know which. The aftermarket has already solved the problems and GM will likely get around to it at some point. I have an F150 10-speed as well, which I like better than my 2023 Yukon Denali's. Not enough miles on either to form a longevity opinion.

 

[SunRunner239]

First post on the forum.. I'm considering a 2025 Yukon Denali with the LZ0 Duramax, as I have an opportunity to order one to spec for several thousand off sticker. I'm looking for a 3 row family hauler that is safer, reliable and isn't awful on gas. I started considering the Yukon since it has the 3.0L Duramax which I perceived to be more reliable (and definitely better on fuel), although what I have been reading has me concerned on the reliability front and makes me wonder if the '25 6.2L is more sensible considering the dealership I am working with provides gas engine vehicles (but not diesel) with a lifetime powertrain warranty for the original owner (I'm aware of the 6.2L recall for '21-'24). The additional maintenance and DEF don't scare me, I just don't want to opt for the LZ0 to find it's not an improvement over the V8 from a reliability standpoint. The truck would see a lot of local trips around town, but highway miles as well. No towing.

I was previously considering a Toyota Grand Highlander Hybrid before I warmed up to the Duramax idea. The fuel efficiency of the LZ0 is impressive, and I like the idea of a full size truck. I've owned several GM vehicles (most recent new was a 2023 Z06, since sold) but this would be my first diesel. Here are a couple of questions after some time browsing the forum, and I'd certainly appreciate being told that I'm looking at the wrong vehicle if that is the case.

1. I've read about people reporting the LM2 having some issues - is the consensus that the LZ0 has sorted at least some of these out?
2. Is oil consumption an issue with the LZ0?
3. I've seen people recommending catch cans. Is this a real problem?
4. Is there some kind of 4,000 mi learning period that goes beyond break-in?
5. Have there been any transmission issues with these trucks?
6. Are you able to buy a GM Platinum 8yr extended warranty (or anything better, if it exists) for the 3.0L Duramax?
7. I'm looking at the Denali reserve package - is the air ride suspension a noticeable improvement over the standard suspension?
8. Have the retractable running boards been problematic on recent builds?
9. Any other things I need to be mindful of?

I really like everything that the truck offers on paper and would likely love it assuming it is pretty reliable, but I do not want to drop this kind of coin and buy myself a headache. If that is the likely outcome, I'd rather spend a little more than half the money on the Grand Highlander Hybrid.

I picked up our 2025 diesel Z71 at the end of Aug... now we have about 1500 miles on it and love it. Only ran 1x 500 mile trip at this point, but will be going on a 1600 mile one soon.

I've seen several threads regarding catch cans also, so wondering applicability for our LZ0 motor. J&L does not look to have a model for the LZ0, but VSE has one for the LM2/LZ0. Don't want to void a warranty, but seems to make sense seeing what people are catching in the can.

Open to thoughts...

 

[Flathead40]

We recently traded in an Expedition Max for a Yukon XL AT4 with the LZ0 and have been impressed so far. Averaging 23mpg over the 1st 6k miles. Only thing I miss from the Expedition is the performance of the 3.5 ecoboost. The build quality on the 22-24 Expeditions was atrocious, and it road like a runaway covered wagon. DEF usage is about 1 gal per 1k miles. GM covered 1st service, but it would have been $75 which is not bad. Winter is coming up so we’ll see how that goes but the others around that have this engine have not had issues. If it wasn’t for this engine we might have stayed in an Expedition.

 

[CTown Duramax]

Get the diesel. Get the diesel. My LM2 gets stronger all the time, now at 44k trouble free miles. I have an early 2021, so the main seal had to be replaced, but leakage was barely perceptible and fixed under warranty with a three day turnaround and a loaner. This engine is very strong. Car magazines report acceleration 0 - 60 at 7.8 sec, 6000 lbs 4WD. I think it is probably faster than that. Maximum 460 lb/ft torque at 1,500 rpm all the way past 4,000 means that movement is effortless. This thing never breaks a sweat, smooth and quiet and it does not run out of breath at higher speeds. Don't worry about DEF. About 4 times a year, I pull into a truck stop and pump DEF for $4/gal. I am experiencing my best milage at moderate to cool atmospheric temperatures, say 50 degrees F and 50% humidity. I have seen 35.1 mpg going from Boston to Albany over the Berkshires traveling the 65mph speed limit on cruise control. I drive 75 - 80 going to Rhode Island and back every week and get 32 mpg without thinking about it. In town depends on traffic, but 16 - 22 mpg is the norm. The diesel is just a better engine. Diesel fuel is everywhere. Don't hesitate. Turbo replacement has not been an issue on the pick up trucks. Modern turbos last and last.