LZ0 Duramax Decision - Input Requested

[sdp9427]

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.

 

[Stbentoak]

As a past and future owner, I'll try to help you.....About 40K miles on my current unit.

#1 LZ0 is supposed to be a new and improved version of LM2 which is already proven dependable product. As long as it has no manufacturing defects there's no reason to think it won't be as good or better than the previous version.
#2 On my LM2 I dump seven quarts in, change oil, dump 7 more quarts in. Never moves on the stick.... have never added oil... hardly even check it anymore. Always full to the top. No reason to think LZ0 will be any different.
#3 Never used one.... could be more pertinent on gas models than diesels. They can't hurt anything, but I see no need for it... hasn't affected anything on my vehicle how it's ran etc.
#4 Not that I'm aware of other than probably the first 500-1000 miles very your speed and go easy on things, I pretty much drove it as I seen fit right out of the box, didn't tow with it for about 6 months, but other than that it had no early indications of break in issues. Did change the oil at about 2500 miles since it was free from the dealership.
#5 Yes but they're the same issues for gas and diesel. Got the recall, got the software installed, kept motoring.... don't expect it to be a huge issue, but if it is it's covered.
#6 Yes you most likely can, you can go as little or as wild as you want with extended warranties. But it does come with a 6/ 100 warranty on the engine and drive train. I'd be less worried about the actual drive train than I would be about any other little thing that could go wrong especially infotainment, et cetera.
#7 Yes, it is a huge improvement, mine has been flawless on my 21 and I wouldn't own one without it.
#8 Mine haven't missed a lick in 4 years. Although if you're working in a lot of wintry conditions, they possibly could be problematic. I keep mind cleaned out and lubricated.
#9 LZ0 could possibly use a little bit more DEF than the LM2, but unless you're towing not noticeably more. DEF gets overblown as a diesel issue, I mean it costs you maybe 25 Bucks a year if you're not towing and you dump it in in 5 minutes, how big a deal is that?

Overall, this vehicle has been everything I expected and wanted it to be. I've short tripped it for weeks on end, I've drove it 1000 miles in a day. It's done every single thing I've asked without a whimper. Fuel economy has been anywhere from 22 miles to a gallon up to 32 miles a gallon, and we don't baby it. If you need the interior space, and you do a lot of road trips, there is no finer vehicle, with no better range, room to haul 7 to 8 people and a cargo area that's cavernous. I can only hope the next one coming in, in a month, will be as good as the one I've had. I was willing to pop north of six figures for the next one. So that should tell you something and I hope to keep this incoming one for a long time.

 

[DuraYuk]

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.

We have had both a 23 lm2 and a 2025 lz0. The lm2 we put about 35k trouble free miles. The lz0 is new so only about 800miles in.

1.) Lm2 issues were early on. Some wiring issues etc. All have been fixed. No issues to report yet on lz0. With that said these diesels are the most reliable PowerPlant so far in the full size gm suvs.
2.) Oil consumption was never a issue for us.
3.) Im a former gm tech. People do dumb stuff all the time and convince themselves it's correct. Your results may vary.
4.) Eh....the transmission learns but that's really it.
5.) Transmission is stout. There's some people talking about valve bodies but I dont see much motion there. My best friend is still a gm Trans tech at a volume dealer and he doesnt see any issues either.
6.)gmpp is the oem extended warranty and yes you can buy it.
7.) We had standard suspension before and have mag and air ride in the at4. It's smoother for sure. Nothing earth shattering tho. Self leveling when towing is sweet tho. No sag.
8.) Had normal running boards before. Have the power ones now. They give a little when my 210lbs steps on them but work fine. It's not rocket science.
9.) It gets stupid good gas mileage and the range is sweet.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving responses from the knowledgeable folks on this Forum.

I cannot personally assist you with your question, having never owned a diesel, but other members of this Forum are chiming in.

 

[PPV_2018]

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).

just wanted to say that sounds all fine, so long as the dealership doesn’t go belly up or sells out to another dealer because if so they probably don’t and won’t honor that. Dealers sell out all the time, even big name high volume sellers so, i wouldn’t rely on something like that .

 

[PPK_]

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.

6- i did a gmep 72k/7 year. I won’t have it past that time.. but every oil burner i have had has something crap out. This is my first gm oil burner though.

Lucky for me i ended up with a 2025 slt… 3.0 instead of a 6.2

Yikes. I would get the 3.0 and move on.

I have a 2025 slt truck 3.0 and a sept 2024 yukon with a 5.3. My 5.3 had a lot of crap in the first oil change… like the tooling building it is gone on it. The 3.0 was clean.. like the 5.3 did in 2018… Get the newer engine.

 

[Stbentoak]

just wanted to say that sounds all fine, so long as the dealership doesn’t go belly up or sells out to another dealer because if so they probably don’t and won’t honor that. Dealers sell out all the time, even big name high volume sellers so, i wouldn’t rely on something like that .

These dealer lifetime warranties are just rife with conditions and terms like oil changes twice as often as the factory recommends and only at their place and all service to the vehicle must be performed at their place for the lifetime of the vehicle for it to stay valid. Hardly anybody can conform to the conditions they set, but nobody reads the fine print until they find out oh you violated the term so no warranty for you....