3.0 Duramax vs 6.2L V8 - which option is best?

[NCB_’22AT4]

Does one really buy a pickup for good mileage? Guess I’m one that enjoys SMILES per gallon instead! The 6.2l provides just that.

 

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[Barbersboy]

For me the 3.0 was a no brainer. I had nothing but trouble with the lifters/rods in the 6.2 and after having it rebuilt twice in 3 years I decided enough was enough-no more gasser for me. I know the 3.0 has its potential issues as well, but having experienced engine failure twice in the 6.2 I moved on. I love the 3.0. As others have said its not as fun to drive but damn is it smooth. Also I might add the MPG is not as good as everyone says. Its ok, but not the huge numbers everyone boasts about. I think I got 27 mpg once driving at the perfect speed with a tail wind....I get about 19-20 in town which I am happy with.

 

[Air Bear]

I had the 3.0 in the Chevy Trail Boss which I guess is the equivalent of the AT4 minus a little luxury. The ride was fantastic and it pulled well too. Power was quite ample for me. I traded it in on a GMC AT4 2500HD because towing my camper was squirrelly with the suspension of a 1/2 ton. I got better mpg towing my camper with the 3.0 than I did with the 6.6 ! Suspension of course was no match. With the Trail Boss I easily averaged 25-26 with a mix of highway and city driving. People who argue that the price equal out at the pump due to having to add DEF and additives are way off. Even adding all of these and pricier fuel you will spend less at the pump. Maintenance will be the heftier cost over time. That was my favorite truck ever. I miss it every time I drive my 3/4 ton.

 

[Air Bear]

I had the 3.0 in the Chevy Trail Boss which I guess is the equivalent of the AT4 minus a little luxury. The ride was fantastic and it pulled well too. Power was quite ample for me. I traded it in on a GMC AT4 2500HD because towing my camper was squirrelly with the suspension of a 1/2 ton. I got better mpg towing my camper with the 3.0 than I did with the 6.6 ! Suspension of course was no match. With the Trail Boss I easily averaged 25-26 with a mix of highway and city driving. People who argue that the price equal out at the pump due to having to add DEF and additives are way off. Even adding all of these and pricier fuel you will spend less at the pump. Maintenance will be the heftier cost over time. That was my favorite truck ever. I miss it every time I drive my 3/4 ton. View attachment 32694

Forgot to mention that the truck I owned prior to the Trail Boss was a 2018 Tundra with the 5.7. I liked the baby max better.

 

[Bidcaller34]

I am making the move from a Tundra to the the AT4 or AT4X. I have Mercedes Sprinter that has the diesel. I'm fine with DEF and I like the mpgs that motor gets (four-cylinder). I do not tow, but I drive a lot. We also make family camping trips and pleanty of Mammouth trips in the winter. I don't plan on building out the truck and will keep it pretty much as is.

I'm on the fence about which motor to get. MPG is really important considering I've been puking money into gas in the Tundra that deson't get great mileage. I was hopign to get some feedback and opinions from folks up here that can give me some insight to both motors. What is your real-world MPG? I live in San Diego so cold weather really isn't an issue. If ya'll can let me know what you like / don't like about your motor and what you recommmend, I would greatly appreciate it.

Thanks - T

I bought the 2023 3.0 Duramax new. It was awesome. I am a traveling auctioneer and mileage is important. I regularly got 32-34 on the road. I recently sold the 23 and bought a 2025. My mileage isn't quite as good but it hasn't fully broke in yet. I got 28 last week going to Prescott AZ and back. So comfortable and that kind of mileage is awesome for me. I also pull a travel trailer. Mileage drops off significantly but that is expected. The exhaust brake is a game changer. I got 11.9 MPG going to the mountains and 17.9 coming back. Love the truck.

 

[MikeDAV8r]

Was originally going to go with the 6.2 until the 3.0l diesel was announced. I took one for a test ride when they first started showing up and was sold. From towing to across country trips it hasn't disappointed, I have a '20 1500 AT4. Great on fuel, very easy on Def when regular running, towing will use more of course. Summer fuel under 70mph have seen 35mpg, over 80mph mid 20's highway running. Take both out for test ridi was

Does one really buy a pickup for good mileage? Guess I’m one that enjoys SMILES per gallon instead! The 6.2l provides just that.

I was on the fence with this very scenario. Had (mental) issues w the scare of the 6.2 nightmare I had read over and over. Then I learnt from my racing buds that the 3.0 Duramax uses an internal belt instead of a solid chain or gear to drive the oil pump, which is retarded, so I ultimately went w the 6.2. That belt over a LONG time WILL fail without warning or can fail prematurely under particular working conditions….and obviously be a major bummer, while the 6.2 for ‘25 has been fixed. I’ve got the active exhaust on mine, crazy HP, more towing capacity, instant goooo, (no lag) and the big one for me, NO DEF! I had a 22 1-ton Duramax big dog. She was a beautiful ride, but got tired of the unreliable and unnecessary DEF requirement. (BTW, is going away). AND I don’t give a rats ass about MPG, it’s a PU!
Bottom line, the oil pump design for the Duramax and the re-engineered 6.2 made my choice easy. And my gawd, the 6.2 has crazy power bolted onto the fake Allison 10 sp trans. Either is a good choice, you’ll be back in the shop regardless of power with the stoooopid electronic updates and TSBs that plague GM. THOSE ARE REALLY A PITA

 

[Cocoabean]

Does one really buy a pickup for good mileage? Guess I’m one that enjoys SMILES per gallon instead! The 6.2l provides just that.

I wouldn't say anyone buys a pickup for MPG, but when comparing two options where one offers 25% higher fuel efficiency with more torque at a much lower RPM its worth debating. In CA where gas and diesel are about the same price and often diesel is cheaper, the 3.0 makes a lot of sense. That's why I went for it.

Plus, the muscle car is for SMILES per gallon anyways.

 

[Hulluvatime]

If you want mpg and higher resale, get the baby D. Sportier and great sound, get the 6.2. I love my baby D and have had a 6.2, which I loved also. I think the baby D is plenty quick, but more HP and lb/ft are easy to get with a few mods.

 

[Falconturns]

There is an X factor in this discussion. If you're towing at altitude, then the diesel is your only option. Having the turbo push more oxygen into that motor allows you to pull much easier. The added torque on the steep grades is a huge plus as well. The gassers are constantly hunting for the right gear, and just run out of air up high. I towed my 5000lb trailer out to Yellowstone 2 yrs in a row. The first year I had a 6.2 and I was struggling to keep gears, and had my foot to the floor at 10,000 ft. I traded that truck in on a diesel, did the same trip the next year, and I set the cruise at 80mph and it was a dream. Pulling up Hwy 14 in the Big Horns was no problem. I'll never drive a gasser again.

 

[Hulluvatime]

Does one really buy a pickup for good mileage? Guess I’m one that enjoys SMILES per gallon instead! The 6.2l provides just that.

Yes! I pull a boat a pretty good ways, haul stuff, put a tent over the bed and will drive to the national parks with it. Mileage matters to me.

 

[Hulluvatime]

I am making the move from a Tundra to the the AT4 or AT4X. I have Mercedes Sprinter that has the diesel. I'm fine with DEF and I like the mpgs that motor gets (four-cylinder). I do not tow, but I drive a lot. We also make family camping trips and pleanty of Mammouth trips in the winter. I don't plan on building out the truck and will keep it pretty much as is.

I'm on the fence about which motor to get. MPG is really important considering I've been puking money into gas in the Tundra that deson't get great mileage. I was hopign to get some feedback and opinions from folks up here that can give me some insight to both motors. What is your real-world MPG? I live in San Diego so cold weather really isn't an issue. If ya'll can let me know what you like / don't like about your motor and what you recommmend, I would greatly appreciate it.

Thanks - T

Check out the Chevy versions also. I have the AT4 and don't like the stock soft Rancho shocks and the stiff seats. Changed the shocks out for Bilstein 5100s, much better. But the seat is still not very comfy. The ZR2 has better shocks, better seats, front locker. I screwed up! But I still like the AT4 looks best.

 

[teshred]

I have the 2024 1500 AT4. On ski trips Los Angeles to Mammoth the 3.0 averages 26-30mpg. On the flats, under 65mph, the milage is 34mpg. I don't tow anything and no modifications yet. I love the comfortable seats and smooth ride.
Good luck!

 

[xOperator]

Nevada is a 2A friendly State. You could always get into HK firearms. I recommend a P7M13 as your first handgun...you'll catch the bug.

You'll be in class 3 firearms in no time!

After picking up a pair of Zenith/MKE MP5Ks during their initial imports few years ago, I finally picked up the HK SP5K-PDW.
Now, I'm afraid to shoot it, and its been designated my first safe queen, hehe

After moving to Nevada, the first thing i did was splurge on Class 3 toys

 

[Hatche90]

If you're looking for a throw-you-into-the-seat, great passing power, throaty-sounding truck, get the 6.2L. If you're looking for better mileage and need a little more towing grunt truck, get the 3.0L.

I've had both (currently have the 3.0L), and that's about as simple as I can explain them. Love the mileage of the Babymax, but I think in the next truck I'll go back to the 6.2L for a more sport-like feel. I miss the growl of the 6.2L.

An easier way to put this, trucks aren’t meant for racing, they are meant for towing. So, get yourself a diesel with torque instead of a gas guzzling motor for horsepower. If hp is want you want then get a sports car.

 

[Hatche90]

Was originally going to go with the 6.2 until the 3.0l diesel was announced. I took one for a test ride when they first started showing up and was sold. From towing to across country trips it hasn't disappointed, I have a '20 1500 AT4. Great on fuel, very easy on Def when regular running, towing will use more of course. Summer fuel under 70mph have seen 35mpg, over 80mph mid 20's highway running. Take both out for test ride

Are you seeing 35mpg on the 25, 50, or 400 mile range setting?