24/25 Diesel vs Gas Reliability

[dkad260]

I like these 3.0 diesels, considering one down the road. My only setback is the fuel price which seems to be negated for now, and the oil pump belt service. What has been the average repair cost for this? Even at that point, you would be wise to replace the rear main seal and anything else you can easily swap.

Not a deal breaker, but a factor for sure.

 

[Polo08816]

For long term reliability and cost of repairs/maintenance, the 5.3 gas should be lower than the 3.0. I think we can pretty much rule the 6.2 out now with all the problems GM has been having. The lifters on the 5.3 could be problematic over time, but I feel there's less data of the 3.0 outside of warranty.

As a home DIYer, I'd much rather work on the 5.3 than the 3.0.

 

[CrashTestDummy]

Just keep the oil and filter changes up to date. Not necessarily at 3000 miles, but not until the 'change engine oil' light comes on, either. We've had great service out of our 5.3's. There were a couple of hiccups along the way, but otherwise a good, solid drivetrain in both vehicles. Our 2002 Duramax 2500HD has been about the best dam vehicle we've ever owned, in spite of the 'problematic' LLY engine. That said, we did opt for the 6.2 on our new Sierra 1500. It's replacing the '02.

We specifically did not want the 3.0L 'Little Dmax'. My personal opinion is that manufacturers have loaded way too many emissions controls on the diesels these days to make them dependable. Sure, the 3.0 may go a million miles, but that DEF sensor that continues to fail will put the vehicle in limp mode, at best.

 

[Stbentoak]

We specifically did not want the 3.0L 'Little Dmax'. My personal opinion is that manufacturers have loaded way too many emissions controls on the diesels these days to make them dependable. Sure, the 3.0 may go a million miles, but that DEF sensor that continues to fail will put the vehicle in limp mode, at best.

I bet there's about 750,000 people out there right now that wish they would have picked the 3.0 versus the 6.2. I can change a sensor in about 1/2 an hour. I'll put my money on the Duramax....

 

[Polo08816]

Just keep the oil and filter changes up to date. Not necessarily at 3000 miles, but not until the 'change engine oil' light comes on, either. We've had great service out of our 5.3's. There were a couple of hiccups along the way, but otherwise a good, solid drivetrain in both vehicles. Our 2002 Duramax 2500HD has been about the best dam vehicle we've ever owned, in spite of the 'problematic' LLY engine. That said, we did opt for the 6.2 on our new Sierra 1500. It's replacing the '02.

We specifically did not want the 3.0L 'Little Dmax'. My personal opinion is that manufacturers have loaded way too many emissions controls on the diesels these days to make them dependable. Sure, the 3.0 may go a million miles, but that DEF sensor that continues to fail will put the vehicle in limp mode, at best.

You can probably make most engines go a million miles as long as there are no limits to what you would repair/maintain.

I bet there's about 750,000 people out there right now that wish they would have picked the 3.0 versus the 6.2. I can change a sensor in about 1/2 an hour. I'll put my money on the Duramax....

Yup, but that's largely the fault of GM for their execution. Other domestic brands as well as GM make reliable NA V8 engines like the 5.3L L84 and the 5.0L Coyote. It's a lot easier getting to components in NA V8 engines than it is in most turbocharged applications. Diesel emissions increases that complexity.

 

[PPK_]

Hello everyone. We currently have a Toyota Sienna hybrid van. We love it in many ways, but miss having a full size suv that sits higher off the ground etc. We are considering a new suburban or Tahoe/yukon. One major area I want to ask about is overall reliability. Would you all recommend the gas 5.3, gas 6.2, or the diesel the most for reliability? Also, what issues have you seen or heard of in the gas and diesel ? Let me know your thoughts and recommendations and experiences.

I have had diesels.. and everyone has let me down.. i had one vw where i had to remove the head-just to change an igniter.. it had big deposit on it…. They are a lot of maintenance…

On the other hand.. i have a ‘25 slt 3 and a 5.3 yukon ‘24… the first 500 mile oil changes are below.. i am telling you.. get the diesel. I think the 5.3 tooling is way past due for upgrading.. or they are not processing/cleaning anything. Oil burner… new tooling.

 

[DenaliCountry]

Just keep the oil and filter changes up to date. Not necessarily at 3000 miles, but not until the 'change engine oil' light comes on, either. We've had great service out of our 5.3's. There were a couple of hiccups along the way, but otherwise a good, solid drivetrain in both vehicles. Our 2002 Duramax 2500HD has been about the best dam vehicle we've ever owned, in spite of the 'problematic' LLY engine. That said, we did opt for the 6.2 on our new Sierra 1500. It's replacing the '02.

We specifically did not want the 3.0L 'Little Dmax'. My personal opinion is that manufacturers have loaded way too many emissions controls on the diesels these days to make them dependable. Sure, the 3.0 may go a million miles, but that DEF sensor that continues to fail will put the vehicle in limp mode, at best.

All new diesels have the emissions controls that create potential reliability issues, but none of those will cause catastrophic failures as far as I know. I don't gather from the OP's post that he's looking to buy an early 2000's lumber wagon. I had an '03 LLY and agree that truck was amazing and I also had a 2012 with an LML in it with all the emissions stuff and it was equally as trouble free for the time I owned it. But I am guessing neither are in scope of what the OP is looking for.

 

[DenaliCountry]

I would pick up the 5.3 or 3.0 diesel... as soon as possible. GM will be putting a Stop Sale on all Tahoe/Yukons with the 6.2 engine at dealerships Monday.

Rumor has it, they don't have the parts to fix all the 6.2's. GM just wants them off the road as quickly as possible.

I don't know about the stop sale, but I would second jumping on a new 5.3 or 3.0 sooner rather than later as I would guess demand for those engines will increase significantly as people start unloading their 6.2's (like I did!).

 

[DenaliCountry]

I have had diesels.. and everyone has let me down.. i had one vw where i had to remove the head-just to change an igniter.. it had big deposit on it…. They are a lot of maintenance…

On the other hand.. i have a ‘25 slt 3 and a 5.3 yukon ‘24… the first 500 mile oil changes are below.. i am telling you.. get the diesel. I think the 5.3 tooling is way past due for upgrading.. or they are not processing/cleaning anything. Oil burner… new tooling.

Are you using 0W20 oil in your 3.0?

 

[PeepValve]

My personal experience, I owned a 2021 Yukon 6.2 until 120k miles and never had an issue. I decided to get the 3.0 diesel in my 2025 for fuel range. The 6.2 has a little more giddy-up, but I never used it, and the 3.0 has plenty of punch.