Fuel mileage expectation on 2500 Duramax ZR2?

Big_dog

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Hello!
Curious to what everyone with the Duramax is getting for in town and highway mileage?
I only have 390 miles on mine as of today. on the way home from the dealership last week I think I was around 15h16 average. That was 90% freeway driving at 75mph. Since I've been home I've only driven 200 miles, mostly in town. I pulled my 5,000# boat a few times but only about 15 miles round trip each time. Right now my average is showing about 8.4mpg and that just seems odd.
I filled up Monday with only ¼ tank left and had only gone 340 miles on ¾ tank of fuel in total. When I'm on city roads doing 35 the instant average shows me getting 7-10mpg unless I completely lift my foot off the gas. I know the computers aren't super accurate but the reality is I still only got 340 miles out of ¾ tank and that didn't seem right to me at all! I just rode with a friend who has the 23 Z71 version and we went over 600 highway miles before ever needing to worry about refueling. Wanted to see what you guys think though. Sorry for the long winded post!
 

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I have no idea on the mileage. But I will say a Duramax needs broken in. It will burn a little oil and get worse mileage for atleast the first 1k miles. Honestly also you shouldn't be towing with it already either. Typically you try to put 1k-1500 miles on a new truck before towing.

Another thing is I always try to vary the RPMs and speed during atleast the first tank or two. IE not setting the cruise on a highway and running a constant speed. I was always taught to vary the RPMs. Basically drive around town or on back roads.
 
Nice rig!

Mine ain't much better at about 8.7 mpg, but I wasn't expecting much right away.

I've only got about 165 miles on it mixed city and freeway. I've also had it idling some when I've been adding some accessories and doing some testing.

With the HD ZR2, you're turning some heavy tires/wheels and running a 4+ inch lift. Physics is not on your side starting and stopping in city traffic and at 70 -80 mph you're essentially pushing a barn door through a hurricane.

I would expect 15-17 mpg city and 18-22 mpg highway. If your towing heavy, say 12-15k, then 10-12 mpg. I've ran enough of the Durmaxes set up this way and that's what I got. My previous rig with 6 inch lift and 35s was best at 68 mph cruising down the highway and I could pull 18 mpg. There were definitely times Ive seen better, but that's realistic with choked up emissions systems.
 

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If you were running a regular HD setup with 275s and no lift you'd see 2 to 3 mpg better.

My neighbor has a 22 with same motor. He hit 50k miles and he swears all of a sudden it runs better, stronger, and gets better mileage now. I've heard others say that, but hadn't been my experience.
 
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If you were running a regular HD setup with 275s and no lift you'd see 2 to 3 mpg better.

My neighbor has a 22 with same motor. He hit 50k miles and he swears allmof a sudden it runs better, stronger, and gets better mileage now. I've heard others say that, but hadn't been my experience.
They aren't really even broken in until around 20k lol. Atleast that's what I've always been told. It really does take a few thousand miles for the mileage to settle in. Atleast that's been my experience. I don't know about 50k, but I swear mine seem to get better after 10k+
 
@AXE - on these new ones, can u tell on the display when they are doing passive or active regents? Been my experience that will tank mileage as well.

Agree with the overall sentiment, break it in a bit more and see where you’re at, doubt you are too far off given your mileage to date. Nice rig, congrats!
 
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Not sure if there's a read out or notification, but I hope so. I could easily tell on my other one by watching rpms, instant mileage would drop, truck was a little sluggish. Mileage would drop 2-3 mpg easily for 35 miles. Mine would regen about 400 miles in city and 500 to 600 miles highway. I tracked them closely and recorded them.

I guess I'll need to see what happens after a few hundred more miles.
 
Hello!
Curious to what everyone with the Duramax is getting for in town and highway mileage?
I only have 390 miles on mine as of today. on the way home from the dealership last week I think I was around 15h16 average. That was 90% freeway driving at 75mph. Since I've been home I've only driven 200 miles, mostly in town. I pulled my 5,000# boat a few times but only about 15 miles round trip each time. Right now my average is showing about 8.4mpg and that just seems odd.
I filled up Monday with only ¼ tank left and had only gone 340 miles on ¾ tank of fuel in total. When I'm on city roads doing 35 the instant average shows me getting 7-10mpg unless I completely lift my foot off the gas. I know the computers aren't super accurate but the reality is I still only got 340 miles out of ¾ tank and that didn't seem right to me at all! I just rode with a friend who has the 23 Z71 version and we went over 600 highway miles before ever needing to worry about refueling. Wanted to see what you guys think though. Sorry for the long winded post!
It takes about 20,000 miles to break in a diesel. They are meant to pull hard from new and work their entire operating life. It takes hard pulls to keep the DPF filter clean. A lot of frequent easy trips will result in more regens and poorer mileage. I think you will see an increase in mileage after that point. Of course as Axe stated, big tires and a significant lift will lower mileage somewhat.
 
That’s a sweet rig. I was at my dealer for service to my 2022 ZR2 this morning and they had a white 2024 2500 HD ZR2 on the floor optioned out on the sticker at $87,905. That truck is a beast. I was curious about the mileage myself since the sticker did not say. It only states C- for greenhouse gas rating an C+ for smog rating. Sales manager said Chevy is only making 50 units which sounds like BS to me. When I hear rare that means reg flag on the $ front. Just turned 16K miles in 10 months and my 2022 has been flawless but this truck really caught my eye. Enjoy it in good health.
 
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Nothing rare about them, the GM inventory shows 472 available or in transit. I'm sure several have been sold for orders. There has been 400+ since about the beginning of October, so they must be pumping out 50 per week.


 

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Nothing rare about them, the GM inventory shows 472 available or in transit. I'm sure several have been sold for orders. There has been 400+ since about the beginning of October, so they must be pumping out 50 per week.


Thanks. I figured it was BS . Just didn’t make sense.
 
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Thanks. I figured it was BS . Just didn’t make sense.
Trust me, I know! I ordered mine, waited 2 months for delivery, was very specific about what I would pay in writing, then they still gave me the line "this is a special truck"! I said my Dad found a loaded Ram 2500 Laramie Longhorn in SD for $8k off MSRP and that truck is special to me. Dealers always trying to stick it to you.
 

Trust me, I know! I ordered mine, waited 2 months for delivery, was very specific about what I would pay in writing, then they still gave me the line "this is a special truck"! I said my Dad found a loaded Ram 2500 Laramie Longhorn in SD for $8k off MSRP and that truck is special to me. Dealers always trying to stick it to you.
I paid 5k under MSRP. I eventually negotiated an increase of 5k on my trade in over their initial offer to close the deal. Drove 2 hours to get there and when they laid the final paperwork out I'll be damned if it wasn't based on MSRP🤬. I had been working the deal for 9 days, driven over 2hr to the dealership and had told the sales girl(literally first month on the job) multiple times that I wasn't driving all the way there to end up paying MSRP because they had the truck listed on Chevy dealership portal at 5k under . It was understood that's what I'm paying. Tried telling me I was paying the lesser amount but I could see all the taxes and everything was based on that MSRP price. Insulting.
I provided a screen shot of the correct price and said they need to honor the advertised amount and quit being dishonest. They left and didn't come back for nearly 45 minutes so I knew it was going to end in my favor. They came back and the new paperwork was based on the correct amount! I ended up with 5k more for my old truck and paying 5k under MSRP on the new one. Felt like a win . The finance guy who finished the papers said I got a smokin deal and could easily go sell the truck for 8-10k over what I just paid. I'm sure he's full of it because the house always wins. At least it felt like I didn't get totally bent over so I'll call it a win.
 
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It takes about 20,000 miles to break in a diesel. They are meant to pull hard from new and work their entire operating life. It takes hard pulls to keep the DPF filter clean. A lot of frequent easy trips will result in more regens and poorer mileage. I think you will see an increase in mileage after that point. Of course as Axe stated, big tires and a significant lift will lower mileage somewhat.
Maybe I need to reconsider my 2500 ZR2 with the Duramax :unsure: If I'm lucky, I'll put about 7000 miles a year on her...keep her for 1-2 years max and then move onto my next adventure. The only thing keeping me in the game is the hope that I may actually make money off this rig when I do decide to trade her in with super low mileage which is why I opted for the Duramax over the gas engine (which I have heard is VERY good but resale may suck the big one).
 
Maybe I need to reconsider my 2500 ZR2 with the Duramax :unsure: If I'm lucky, I'll put about 7000 miles a year on her...keep her for 1-2 years max and then move onto my next adventure. The only thing keeping me in the game is the hope that I may actually make money off this rig when I do decide to trade her in with super low mileage which is why I opted for the Duramax over the gas engine (which I have heard is VERY good but resale may suck the big one).
I think the diesel will have better resale, but it costs about $10K more retail. The oil and fuel in a diesel act as lubricants and the low RPM of the engine make for a slower break -in period. That's one of the reasons diesels last so long. I think with todays operating cost and the after treatment on the exhaust side, I believe it takes over a 100,00 miles to start recouping the added cost to operate them. Diesel exhaust fluid is another operating cost to factor in. I like diesels, but I don't have use for one anymore. These new gasoline engines have a lot of power, especially at near sea level where you are located. It's definitely a personal choice.
 
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I paid 5k under MSRP. I eventually negotiated an increase of 5k on my trade in over their initial offer to close the deal. Drove 2 hours to get there and when they laid the final paperwork out I'll be damned if it wasn't based on MSRP🤬. I had been working the deal for 9 days, driven over 2hr to the dealership and had told the sales girl(literally first month on the job) multiple times that I wasn't driving all the way there to end up paying MSRP because they had the truck listed on Chevy dealership portal at 5k under . It was understood that's what I'm paying. Tried telling me I was paying the lesser amount but I could see all the taxes and everything was based on that MSRP price. Insulting.
I provided a screen shot of the correct price and said they need to honor the advertised amount and quit being dishonest. They left and didn't come back for nearly 45 minutes so I knew it was going to end in my favor. They came back and the new paperwork was based on the correct amount! I ended up with 5k more for my old truck and paying 5k under MSRP on the new one. Felt like a win . The finance guy who finished the papers said I got a smokin deal and could easily go sell the truck for 8-10k over what I just paid. I'm sure he's full of it because the house always wins. At least it felt like I didn't get totally bent over so I'll call it a win.
That's a decent deal, especially in a new model! I ended up about there myself (-%5 MSRP) , which was low end of the discount I said I wanted when I ordered. I had the pricing saved in my text messages and it was logged into their system at the dealer. They finally gave me it. Like you said they still made a pile, plus they get hold backs, volume checks, all the warranty and service work.

I'm happy and if 5 years down the road it's does as good as my others I'll be even happier.
 
I think the diesel will have better resale, but it costs about $10K more retail. The oil and fuel in a diesel act as lubricants and the low RPM of the engine make for a slower break -in period. That's one of the reasons diesels last so long. I think with todays operating cost and the after treatment on the exhaust side, I believe it takes over a 100,00 miles to start recouping the added cost to operate them. Diesel exhaust fluid is another operating cost to factor in. I like diesels, but I don't have use for one anymore. These new gasoline engines have a lot of power, especially at near sea level where you are located. It's definitely a personal choice.
Thanks Scuba! A few Chevy and GMC dealers all told me the same thing. The way I drive, I will actually make money (based on my deal or have an insignificant loss in 1-2 years). With a gasser, I would take about a $15K hit in trade since most all folks buying these trucks want a diesel. As long as I won't be doing any damage to the diesel by driving a lot of short trips, and only putting about 7K miles/year, it still appears to be the better option financially short/long-term. If I am being BS'd, let me know guys.
 
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I think the diesel will have better resale, but it costs about $10K more retail. The oil and fuel in a diesel act as lubricants and the low RPM of the engine make for a slower break -in period. That's one of the reasons diesels last so long. I think with todays operating cost and the after treatment on the exhaust side, I believe it takes over a 100,00 miles to start recouping the added cost to operate them. Diesel exhaust fluid is another operating cost to factor in. I like diesels, but I don't have use for one anymore. These new gasoline engines have a lot of power, especially at near sea level where you are located. It's definitely a personal choice.
I'm with scubatech on this. I don't think you save or make any in under 5-6 years. There's a bigger market for diesel trucks that are 6-10 years old cause they still have a long life and people can afford them.

Nothing special about this truck and it'll depreciate like every one of them. My neighbor has a 2022 HD and he's been trying to work a deal on a ZR2 and he said the dealers didn't offer him what he thought he should get. It has the same motor and transmission without the new gadgets.
 
Thanks Scuba! A few Chevy and GMC dealers all told me the same thing. The way I drive, I will actually make money (based on my deal or have an insignificant loss in 1-2 years). With a gasser, I would take about a $15K hit in trade since most all folks buying these trucks want a diesel. As long as I won't be doing any damage to the diesel by driving a lot of short trips, and only putting about 7K miles/year, it still appears to be the better option financially short/long-term. If I am being BS'd, let me know guys.
I don't think your being BSd, but it ain't a money making or saving kinda deal.

If I was you, I'd put my money in a CD that can net you 5% with virtually no risk. Wait until they dona ZR2 refresh in 2025 or 26. Tahoes are getting a refresh next year. Enjoy the one you have cause it's got all the same creature comforts.

If you want a better sound system and a phone charger that actually works definitely get the HD, cause that's the only upgrade I've noticed. Still have a radio that cuts out, sketchy Google functions, and yellow stitching.......LOL.
 
Thanks Scuba! A few Chevy and GMC dealers all told me the same thing. The way I drive, I will actually make money (based on my deal or have an insignificant loss in 1-2 years). With a gasser, I would take about a $15K hit in trade since most all folks buying these trucks want a diesel. As long as I won't be doing any damage to the diesel by driving a lot of short trips, and only putting about 7K miles/year, it still appears to be the better option financially short/long-term. If I am being BS'd, let me know guys.
If you get a black with sunroof, multi flex, and tech pkg, call me when you trade…I will be interested 😅
 
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