• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

3.0 Liter Duramax To Get An Upgrade

I used to hand calculate my fuel mileage on my LLY Duramax. I averaged around 24mpg on all highway runs and 18-19 for all other driving. I would have thought the 3.0 liter 6 would have done better.
My last hand calculated fuel mileage run was done last year. From RI to central PA. Doing around 78-80 mph on highway with 198k on the odometer I got 22.4 mpg. And that was with my turbo stuck with vanes wide open. I get about 18mpg around town here still. Not too shabby for a 6.6liter diesel V8.
But as I am getting older I am looking to my next vehicle purchase. Still up in the air. Just have to figure how much the belt change will cost, and how difficult it is.
 
RI Chevy Silveradoman said:
I used to hand calculate my fuel mileage on my LLY Duramax. I averaged around 24mpg on all highway runs and 18-19 for all other driving. I would have thought the 3.0 liter 6 would have done better.
My last hand calculated fuel mileage run was done last year. From RI to central PA. Doing around 78-80 mph on highway with 198k on the odometer I got 22.4 mpg. And that was with my turbo stuck with vanes wide open. I get about 18mpg around town here still. Not too shabby for a 6.6liter diesel V8.
But as I am getting older I am looking to my next vehicle purchase. Still up in the air. Just have to figure how much the belt change will cost, and how difficult it is.
Click to expand...

Wow, your fuel mileage is better on your truck than my Chevy 2500HD. The best I ever got on the highway was 22.8 MPG, that was some 55 mph to 65 mph driving flat ground, no mountains. Generally on the interstate running about 70 mph, I can get from 19 to 20 MPG all day long, that's about it. Local runs here in the mountains, seems like it's 15 to 17 MPG, if I remember correctly, hadn't checked it in a while. Your driving style might be different maybe? I very seldom do jack rabbit take offs, but I will blow the soot out of it ocassionally. Trying to figure the difference in our trucks. I assume yours is similar, I've lost track about yours. Its a GMC, crew cab 4x4, 3.73 rear gears, no camper shell? I've got the camper shell on my truck, empty, it weighs 7,340 pounds If I remember correctly. I've got 3.73 rear gears, 4x4, crew cab and as I mentioned before it's the LBZ motor, 360 HP, 650 ft/lbs of torque if I remember correctly. Maybe if yours is the LLY, it gets better fuel mileage?
 
I have the Chevrolet 2500 HD crew cab. Nothing on the bed. I upped tires and adjusted for size on my tuner. I was shocked that I had better fuel mileage at 75-80 mph than I did at 65-70.
I did use a sheel of plywood to make a Portuguese bed cover for the airflow and to cover my stuff in the bed. That may help lower air turbulence. Provide better air flow across the bed with plywood in place.
My best tank was 24.8 mpg going from RI to Loudon, NH for Nascar race. 4 guys in cab. Hand calculated with 90hp Hypertech tune. Much lower mileage on odometer and turbo was in full working order. Lol
I gotta get that turbo fixed.
 
RI Chevy Silveradoman said:
I have the Chevrolet 2500 HD crew cab. Nothing on the bed. I upped tires and adjusted for size on my tuner. I was shocked that I had better fuel mileage at 75-80 mph than I did at 65-70.
I did use a sheel of plywood to make a Portuguese bed cover for the airflow and to cover my stuff in the bed. That may help lower air turbulence. Provide better air flow across the bed with plywood in place.
My best tank was 24.8 mpg going from RI to Loudon, NH for Nascar race. 4 guys in cab. Hand calculated with 90hp Hypertech tune. Much lower mileage on odometer and turbo was in full working order. Lol
I gotta get that turbo fixed.
Click to expand...

Tuner might just be the difference? Also, for the life of me I dont know why you might have a GMC, after all, your screen or ID name on here has Silverado in it, I'm just not with it today.
 
Just picked up a 2024 3.0L GMC 1500 4x4 CC with 32K on odometer yesterday, so far so good drove 300 miles to go get it, have put 350 on it driving back and local driving last night.

Traded my 2020 GMC "gasser" Canyon on it, liked the Canyon, but Loving this truck so far.

It has room and creature comforts I never dreamed of over the Canyon which was a nice ride, got $22K in trade on it, additional $33K after taxes, extended warranty etc. loan 60 mos @ 3.49% will write off against my consulting company.

Now I need to bone up on possible issues down the road, I already know about the stupid belt drive oil pump design, is there a conversion kit for chain drive for that?
 
Turbine Doc said:
Just picked up a 2024 3.0L GMC 1500 4x4 CC with 32K on odometer yesterday, so far so good drove 300 miles to go get it, have put 350 on it driving back and local driving last night.

Traded my 2020 GMC "gasser" Canyon on it, liked the Canyon, but Loving this truck so far.

It has room and creature comforts I never dreamed of over the Canyon which was a nice ride, got $22K in trade on it, additional $33K after taxes, extended warranty etc. loan 60 mos @ 3.49% will write off against my consulting company.

Now I need to bone up on possible issues down the road, I already know about the stupid belt drive oil pump design, is there a conversion kit for chain drive for that?
Click to expand...

Congrats on the new addition, let us know how it performs. I've really been interested in the 3.0 Liter Duramax, but the extra cost of diesel versus gas has turned me away. At one time I had it calculated as to what kind of fuel mileage the diesel would have to get to even come close to breaking even. Plus that oil pump belt is another deciding factor.

So you traded in that Black Canyon that you had? That was a nice truck I would assume.
 
Yes traded it, it was nice 3rd one down the list here https://www.longlewis.com/used-inventory/index.htm?normalDriveLine=4WD&year=2020 black at 58,8K on odometer, I had mild Trifecta Tune in it usually 26 mpg on highway, 22 mpg avg city/highway combined.

I wasn't really needing new truck Carvana offered 25K on trade, where I bought it, that got me to thinking how much worth after delivery etc trade would be more like 21K, so went local found a 2023 with 13K miles on it, dealer would only give 21K for canyon and woyuld not come off any also was going to add docs fees and that one was 47,400K....I had them pull maint records it had some programming issues, and DPF/DEF flags fixed with software supposedly, stripped down no floor mats/bed liner/ventvisors/ hard trifold bed cover/or running boards I had on my Canyon.

Told them when serious call me back, started looking elsewhere found the 2024 for $43K had everything I wanted except bed cover I will add that, Weather tech vent visors also will add, but paid off 11K I owed on the Canyon, new loan for 3.49% vs. 6% gave me 22K in trade, after all done $33K loan which I will depreciate as company vehicle for my consulting company income. And I have a Diesel with Turbine Doc Technical Services (TDTS) footing the fuel bill, winner-winner for me.
 
You must log in or register to reply here.
Back
Top