Looking at a new vehicle in the near future and the GMC 1/2 ton with the 3.0 really caught my attention.

Who has one?

Mileage? rated at 22 and 26, others talk of closer to 30 real world.
Mechanical issues? Its been around for 2 years now, not exactly long term but whats the word on the street?
looks like an oil change on this motor is about double at the local dealer, 150 bucks????
DEF fluid, how much we paying per gallon and approx what cost per tank of fuel or per MPG?
Any starting issues in cold weather? lowest I might see here is -25 at night once or twice a year.

According to the salesman, about 8 months out, Wowza.

It has my interest also. It is an inline 6 as all diesels for these trucks should be in my opinion. That is a good start. Not to thrilled about it being an aluminum block though. I know it has steel sleeves, but an aluminum block diesel just doesn't feel right to me.

28/30 mpg from a full size truck (1/2) has a lot of appeal, but still haven't crunched all the numbers.

My current 5.3 gas pulls my boat fairly well, no real issues to justify a 6.2 gas or even the 6.0 Daddy Duramax,

Overall lifetime avg about 16 mpg.

No just no. Google some pics of the engine.

This should be good.

Thanks bro, really appreciate your in-depth analysis.

Very helpful.

Well, ya, now that your here.

Any jokes abut my Mother and the need for a diesel, U b off my X-mas card list.

If you order this engine with the 10L80 10 speed transmission you would really have a winner IMO... my son has the 10 speed in his 2021 Sierra with the 5.3 and it is a great set up. With the available additional gearing they can more easily match the driving load to the available power band and it results in a feeling of more power at all rpms, and a smoother transition between gears.. should be even better with this 3.0 diesel...

Kenneth;
Good afternoon sir, I hope the week was a good one and this finds you well.

The 2.8 Duramax was, as far as I am aware, an entirely different engine than the inline 3.0 liter 6 cylinder.

Here's a blurb I found online regarding the 3.0.

"The Duramax 3.0-liter diesel uses a lightweight aluminum block and cylinder head to reduce mass, though the cylinder liners are iron. That’s still a 25% mass savings over a comparable cast-iron block. The main bearing caps are iron, as well, which protect the engine under high combustion pressures while a deep-skirt block (where the block casting extends below the crankshaft centerline) contributes to the strength. Also adding stiffness, an aluminum lower crankcase extension is attached to the main bearing caps."

To begin with my thoughts on that, I'll say I began running diesel equipment on a reasonably large farm in the mid '70's and have been involved with diesels from that time on in varying amounts including Kubota, Mitsubishi, VW, Cummins, Ford, GM Duramax, Perkins, Cat, International and Mack engines - off the top of my head.

My last place of employment before retirement was a GM dealership and I try to stay up to date on what the newer ones are doing, sometimes through a family member who is a certified diesel mechanic.

If I was shopping for a new diesel pickup, the very last thing I'd hope it to have would be an aluminum block for a plethora of reasons, not the least of which is that diesels need heat to burn efficiently and an aluminum block will not retain heat like a cast iron block will.

When I worked at the GM dealership, I got to see first hand how the big 3 dealers struggled with the parent companies attempting to make the new emissions strangled diesels keep running.

I have nothing, as in not one good thing to say about the newer diesel engines in their factory state.

Sorry to be negative, perhaps I'm entirely too jaded from my experiences and it's entirely possible that GM has engineered this new diesel to be perfect and wonderful in it's first edition.

Hopefully that was useful to you or someone out there sir, good luck with the truck purchase whichever way you decide.

Dwayne

I've had a GMC 3.0 4WD for about 1-1/2 years now and 75K miles and love it. It's been leveled and has larger tires than OE tires and it get @ 21 mpg in my driving which is mostly on the road. The bigger tires and leveling really hurt the mileage by almost 6 mpg. I drive over 80 mph on the interstate. With a less heavy foot you will get better mileage as I get almost 25 mpg in roads where I stay around 65 mph.

Oil change and tire rotation every 7500 miles costs about $160 at the dealership. Change fuel filter about every 25k miles. 5 gallon DEF tank is good for 2500 miles.

Love this truck, but if I was mostly driving around town I would probably have a gas burner. That 6.2L V8 engine is a beast and will pass anything but a gas station.

The 6.0 gasser never gets any love.

You don’t want any EPA compliant diesel unless you *really need* a diesel. And if you are looking at a half ton, you don’t really need a diesel.

The 3.0 duramax has a belt that's actually in the oil that is supposed to be changed every 150 000. They have to drop the transmission to get to it. It's about an 8 hour job like changing the timing chain on Hondas.

An engineer at GM said the belt was a compromise because the inline 6 is already almost too long to fit in the trucks. That belt configuration was a way to keep it shorter. I've wondered why they didn't go with a compacted graphite iron block instead of aluminum as well.

I've really been looking at a new suburban and I'm considering this diesel in one. 26 mpg in a suburban sounds pretty good. I drove a 1/2 truck with the diesel and had good torque and decent power. The 10 speed auto is very nice. My cousin said he's sold over 100 trucks with the 3.0 in the last 2 years and only 1 had a problem. It uses oil and had the head replaced under warranty.

I really want the z71 suburban but you can get the diesel in it because of the shape of the front end makes it barely too short. I still wonder if they could have made the motor shorter with compacted graphite iron.

I guess the new version of the ram 3.0 diesel is a pretty decent motor compared to their earlier one. It does have a CGI block but it's a v6 and I like the idea of the straight 6.

The dealer said they can't even order me a suburban with the diesel now anyways. I guess they are offering the 6.2 gas in the z71 for 2022 so maybe I'll go that way.

Bb

The expense of diesel maintenance and parts [if you keep it long term] offsets the fuel economy .

Even when I dragged heavy boat/tractor around I couldn't justify a diesel , plus hated the noise .

The 3.0 with upper 20's mpg sounds good but the long term numbers don't add up for me .

Gas engine w/10 spd. transmission = torque multiplication .
What burleyboy said ...

Get one Kenneth [3.0 diesel] and keep us posted on how it works out .

I have a 2021 GMC Sierra 1500 AT4 with the 3.0 Diesel engine.

I am getting around 24 mpg on the highway at 75 mph. Power is good, I pull a boat that is around 5400 pounds with ease.

I am well pleased so far with one exception. Several times the truck has failed to start. I press the button to start it, the engine turns over for about 10 second but does not start. It will start the second time almost every try. This has happened about 10 times. I bought the truck in March and it has 19,000 miles on it. GM just released a programming update to resolve this.

When my wife’s Expedition is retired, I am considering a diesel Yukon.

Previous to this truck I drove F250s with diesels.

The first time something [bleep] the bed motor related there goes all your fuel savings. Get a gasser.

Fully understood on the added expense with a diesel.

Regarding the noise on the 3.0, very quiet for a diesel, surprisingly quiet.

We have similar boats, what kind of mileage when pulling the boat?

Agreed.

Still run the 93 Dodge Cummins I bought new.
Love diesels. Nothing like them.

Electronic fuel management has been a great thing,
and the manufacturers have done a good job on the reliability of it.
But, the emissions control have reduced performance, decreased mpg,
and hugely affected reliability and cost.

Bought my truck as a personal vehicle that can tow or haul anything
I might want to. Today, I would buy gas unless I was going to frewuently pull
the kind of loads that few ever pull.

Taking it easy, keep it at 70, mixed with time at 55 to 60 mph, you can expect around 14 to 15.

My brother has a 2020 4wd GMC with the 5.3 gas, pulling a similar weight camper he is getting 7 to 8 under similar conditions. There is more wind resistance on the camper. We plan to pull his camper with my truck to compare mileage.

'14 Siverado 1500 4x4. 5.3L, 3:42 gears. close to 90K miles and it still does 21-22 MPG highway at 75 or higher MPH. With a bed pretty well loaded with tools. Does better than that in the summer, if the A/C is off.

Pulled two double axle dump trailer loads of firewood home so far this year. Used to haul wood on my 16" double axle flatbed, but the dump is handier. Don't trailer much with it like I used to, but it pulls whatever is behind it. Oil change/tire rotation runs around $65 at the dealer. Think I'll just stay with what's served me well? My third 5.3L 4x4 since 2006.

Best friend was a diesel mechanic since the late 60s, eventually branch manager at a major chain of diesel repair shops. Not only did he never own a diesel pickup, at one point in the early 90s, he replaced all of their service trucks with 6L GM gassers.
Based on his experiences, switched to a 2500 w/6L in his own Silverados, back when they went to aluminum heads/CI block engines in half tons. His widow is still driving his last new Silverado 2500 6L 4x4. and it's at well over 200,000 miles? She's been pulling a horse trailer with it since it was new.

Most I know who've been driving diesel pickups for years, aren't much impressed with the newer ones.

Years back we went gasoline engines Europe went diesel...last I heard they were fazing out diesel cars in Europe.

Diesel engines put out more pollution...diesel fuel costs more they are more expensive to maintain and work on....unless you are towing something really heavy regularly a Diesel sucks.

I know lots of people that own them.....a buddy told me if you think you need 4x4 with a diesel truck it's too late.

"General Motors Temporarily Halts LM2 3.0L Duramax Diesel Engine Production"

Click Here

Stoppage due to temporary supplier issue.

I have a 21 GMC Sierra AT4 with the 3.0. My fuel range per tank is somewhere between 800 to 820ish per tank. I usually fuel up close to 750 miles. I get between 30-34 mpg driving back and forth to work about 84 miles a day. Great low end and mid range torque, it lacks upper end pull of gas but it’s still no slouch. Quiet and refined for a diesel. Def range without towing is about 10k per 5 gallon tank, if you tow it will be less than that. If your driving like you want good fuel economy you will see it, but if you drive it like a 20yr old male who likes to have fun your mileage will suffer. Definitely glad I chose this engine even over the 6.2 due to fuel prices and performance. Edit….. 7qts of oil and filter change at my dealer is in the $80 range. Def prices at the pump are around $3 a gallon in Pa. Out of the jug online prices are at least $5 a gallon.

30-34 mpg?
11 to 12 hours cruising range.....
oh hell.

Yes, very consistent numbers. I’m not slicing and dicing through traffic in the morning just keeping up with most of it, 55-65mph most of the way.

I had a 2007 Titan with the 5.6 and had to fuel up every 4 days commuting. Now I can go 2 full weeks without fueling if I don’t drive anywhere over the weekend. I have tons of pictures on my phone of my mileage. My best 50 mile avg was 36.something. If anyone wants to see any pics of the range and mileage pm me your phone number and I will send them to you. It’s no BS. My commute is pretty flat with some small hills on the way.

Ken I think you and I texted before. It was about plumbing if I remember correctly. I had pipes that apparently froze and swelled and had a guy make me .686” inside diameter fittings.

The 3.0 is not a loud as the 5.3 or 6.2 gas burner. It's another reason I love the engine.

Correct.

The man speaks wisdom

I'm loving my 3.0 Ecodiesel. Time will tell how it holds up.

GM: aluminum heads, aluminum block, turbo. What could go wrong

Several years ago someone here told a pranking story , I've told that to friends it was really funny to me .

Member here ? - his neighbor bought a Hybrid type car Honda/Toyota [?] to save money on his long commute to work . Member here & another neighbor were sneaking over to neighbors house at night and adding gasoline in small amounts 1/2--3/4 gallon approx. every night . Car got like 50+MPG according to the factory , guy was closely gauging his fuel economy and was tickled pink with the spectacular mileage he was getting . .Told his good friends that his new car was getting far better mileage than claimed . They went along with him -- great
- WOW are you serious comments .

Guy took his new car in for its new car check-up and they stopped putting the prank gas in it - guy was mad - went to the Dealership and made a fool of himself claiming that they did something to his car and demanded they undo whatever they did . Only to later find out that his two great neighbors had pulled a joke on him .

Ford is dropping their 3.0 powersmoke already because they have high hopes for their powerboost hybrid. I went with their new hybrid f150 because I liked the idea of the 7.2 kwatt generator built in. With the Biden regime in office the generator may come in handy soon.

I was talking to a farmer the other day that was trying to get a diesel half ton for himself and a diesel yukon for his wife. He said he has 40,000 gallons of off road diesel he bought last year for 89 cents a gallon. Diesel stores long term much better than gas. I guess he's willing to bet they won't check the fuel in his wife's yukon for color.

Bb

I actually saw a fuel check station near elko. First time I have seen it.

I've owned a diesel truck since 1985 and haven't been checked. I run bio diesel, just mix a gallon or two of used engine oil in your diesel tank and that's that.

That worked in the days before common rail injection, but would be foolhardy to do today.

I've owned diesel trucks sense the first Dodges before all the emission garbage was put on they were great engines .....last diesel was a 2012 Ford F-350 good motor 120'000 it needed that stupid ass muffler replaced part of the emissions $1400 and I needed to do the work....just picked up a 2021 Ford F-250 gas no more diesels for me just get 2 miles to the gallon less a lot cheeper in the long run.....

Just stay away from the 5.3 and 6.2, engines are failing left and right. The folks on the sierra forums have a lot of good to say about the 3.0 though.