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3.0 Liter Duramax To Get An Upgrade

BIGR

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Looks like their boosting the Horsepower and Torque on the so called 3.0 Liter Duramax, along with piston and other part upgrades.

 
Just curious if anyone has any long term feedback. For reliability and durability.

I don't personally know anyone that owns one, but I see a few now and then.

There was alot of discussion about the oil pump belt having to be replaced at some point. Latest info about that (newest engine design) is replace it at 200,000 miles or at 15 years, whichever comes first. I also read a few things about injector issues, not sure how many are having that issue.

Maybe @BoostN will chime in with his experience with it.
 
I had a 21 GMC with the 3.0. I am pretty sure it was the first gen model. The only issue I had with mine was the push to start or remote and starter would crank till time out without motor starting. It would then start every time the second try. I believe it did that about 6 times over the year I had it.

Besides that, no issues. I liked the truck, hated the payment.
 
Was the GVWR increased past 14K#? Tried to look up the spec and it seems that GM is hiding this number.

Did manage to find 2024 towing capacities. The 5.3L gasser was rated to tow more than the diesel. Ouch!

Nope, the 5.3 can tow up to 11,000 pounds, the 3.0 diesel is at least 13,000 pounds. 6.2 gas is 100 or 200 pounds more than the 3.0 diesel, all according to the configuration of the truck.

GCWR for the 6.2 gas is 19,100 pounds.
GCWR for the 3.0 diesel is 19,000 pounds.

My findings based on this chart by Chevy. One would assume that GMC is similar, maybe not?

 
The long running starter issue was on mine that a ECM reflash took care of.. I do have a slight oil leak that I need to get taken care of... other then that it's been a good ride. I will say it's not something I would keep past 120K or so because of the belt change (150K interval I think).
 
Thank you sir.

And of course I find a mistake in the first paragraph. Lol. V8 Duramax's first came with a 5 speed Allison. 6 speed came in 2006. Lol
Screenshot_20240918_080925_Firefox.jpg
 
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Thank you sir.

And of course I find a mistake in the first paragraph. Lol. V8 Duramax's first came with a 5 speed Allison. 6 speed came in 2006. Lol
View attachment 89762

Yes Sir, great eyes to catch that, I didn't read all of the article. Amazing how social media and news media gets things wrong on a regular basis. We could try and correct them, sometimes they claim to know everything and don't give a big rats arse if the information is correct or not.

The reasons I waited till December of 2005 to buy my 2006, 2500HD was to get the LBZ Duramax and the 6 speed Allison. I test drove a Black 2005, 2500HD that had the LLY engine and the 5 speed. It was impressive power wise, but didn't have the extra HP and Torque like the LBZ. I truly believe for its time the LBZ was one of the best options. No particle filter, no regens and no DEF junk to mess with.
 
Yes, I agree BigR. We both know you could give the media a typed article and they would still get it wrong. Lol
My 2006 was an LLY. Just a detuned LBZ, but has all the LBZ goodies inside. Just basically a tuning difference.
 
Yes Sir, great eyes to catch that, I didn't read all of the article. Amazing how social media and news media gets things wrong on a regular basis. We could try and correct them, sometimes they claim to know everything and don't give a big rats arse if the information is correct or not.

The reasons I waited till December of 2005 to buy my 2006, 2500HD was to get the LBZ Duramax and the 6 speed Allison. I test drove a Black 2005, 2500HD that had the LLY engine and the 5 speed. It was impressive power wise, but didn't have the extra HP and Torque like the LBZ. I truly believe for its time the LBZ was one of the best options. No particle filter, no regens and no DEF junk to mess with.
Still is
 
My 2021 averaged 18, will try to post the specs below. Mine was an AT4 with a total of 6 inches of lift on 35" tires.
07/30/21401$56.0019.316$2.899
08/10/21776$56.0019.317$2.89937519.4
08/20/211197$61.0021.335$2.85942119.7
08/31/211588$49.0018.224$2.68939121.4
09/14/212020$56.0020.748$2.69943220.8
09/20/212461$63.0021.731$2.89944120.2
09/24/212908$66.0023.579$2.79944718.9
09/30/213285$61.0020.615$2.95937718.2
10/04/213716$68.0122.677$2.99943119.0
10/07/214097$61.0020.340$2.99938118.7
10/13/214467$60.0020.007$2.99937018.4
10/16/214904$71.0022.984$3.08943719.0
10/21/215239$56.0018.069$3.09933518.5
10/25/215603$59.0019.288$3.05936418.8
10/28/215971$62.0020.267$3.05936818.1
11/02/216304$56.0018.069$3.09933318.4
11/04/216671$60.0019.613$3.05936718.7
11/11/217042$65.0020.446$3.17937118.1
11/17/217391$62.0020.007$3.09934917.4
12/11/217690$48.0016.332$2.93929918.3
2022
01/16/227970$50.0116.189$3.08928017.2
02/26/228335$74.0020.560$3.59936517.7
03/15/228573$60.0012.503$4.79923819.0
03/17/228809$58.0012.238$4.73923619.2
03/21/229082$72.0115.389$4.67927317.7
03/24/229447$95.0120.392$4.65936517.8
05/15/229719$50.0010.003$4.99927227.1
06/05/229958$104.0020.003$5.19923911.9
06/16/2210221$67.0013.402$4.99926319.6
06/28/2210637$106.3021.013$5.05941619.7
07/14/2211073$99.0020.544$4.81943621.2
07/18/2211395$91.0019.122$4.75932216.8
07/29/2211818$100.3422.057$4.54942319.1
08/01/2212212$100.0121.745$4.59939418.1
08/14/2212597$88.1720.228$4.35938519.0
08/24/2213011$97.3622.336$4.35941418.5
09/07/2213350$86.0018.864$4.55933917.9
10/01/2213638$66.0115.500$4.25928818.5
10/30/2214014$96.0120.608$4.65937618.2
12/31/2214323$71.0117.936$3.95930917.2
 
A 1500 Chevy or GMC with the 3.0 Duramax really does interest me, as far as a daily driver lite towing truck. Changing the oil pump belt at 150,000 to 200,000 miles really doesn't bother me. Heck, no more than I would be driving it, that would be 15 to 20 years from now, I'd be in my mid to late 70s, might not even be still on this Earth. I guess though they reccomend changing the belt at 7 years or so regardless of miles, that might not be as fun. So, that might be the deciding factor, heck I might just get the 1500 with the 6.2 Liter gas engine and say the heck with it. Don't think the 6.2 Liter gas is going to be much worse than the 5.3 gas and it would be better towing.

My biggest hang up with it is that unless it gets a bunch more miles per gallon, fuel mileage then what's the advantage over a gas burner other than a possible towing advantage. The closest gap on fuel, diesel versus gas right now is 40 cents per gallon. At one time I had all that figured out as to at what point you would about break even, on the fuel cost.

I watched a guy on the internet the other day, he test drove a Chevy with the 5.3 Liter gas and then he drove a Chevy with the 3.0 diesel. Both trucks were brand new and were identical, 4 wheel drives, same rear gears and all. Somehow he got the dealership to allow him to do a fuel mileage test. He probably worked there and they wanted to drum up some business. He left the parking lot, hit the interstate and probably drove 10 to 15 miles one way, turned around and went back to the dealership. On the interstate he was driving at 70 and 75 mph, sometimes slower according to traffic. He did do a 70 to 85 mph acceleration test also with both trucks. He tried to duplicate the second run which was with the 3.0 Liter diesel truck and was getting slowed down in heavier rush hour traffic. If all things had been the same it could have been a more accurate test? He got held up at a few traffic lights more with the 3.0 Liter diesel truck. Also his MPG figures were strictly based on what the trucks computer was telling him. I like the old method of filling the tank, running a decent route and refueling again method. Don't know how accurate the computer calculations are? Since he only drove a short distance I figure he had to rely on the trucks calculations.

Ok, by now you are saying cut the bull crap, what was his results.

3.0 Liter Duramax was 24.3 MPG.
5.3 Liter 5.3 Liter gas was 18.3 MPG.

I'm sure there are more accurate test out there on the net. The TFL guys are doing those test all the time, one just has to do a little searching.

It is great that Marty and other guys on here can give us some great honest feedback on those trucks, Thanks Marty and @BoostN .
 
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