noharleyyet
Well-known member
Thx for the update...I'm waiting on the '26 models to consider going from my 2500HD to something in a 1500.
GMC purchase mileage question
- Thread starter Papsqueeg
- Start date
Interesting. My 2024 GMC Sierra 1500 with the 3.0 Duramax is at the dealership for the first time this morning due to a warming light. Suspicion is a DEF issue.
It’s been a great truck so far. I’m surprised how much I like it and the diesel engine.
Dealer called. Valve body needs replaced. He said 2-3 weeks as the part is on back order. A little Google searching shows that the valve body going bad is an issue for GM.
It’s covered by warranty. Better for it to happen now than in the fall
Interesting thread a year plus on. My 2500 Duramax keeps on rolling with nothing but reliability. I still like this truck but plan to reload this fall.
My son bought the 1500 GMC with the baby diesel this summer. So far so good (he only has 10,000 miles on it ). He does always spout off how great his mileage is, but did mention that is at 65 mph on the highway. Apparently above that it drops off quickly.
Anyhow, sorry to the folks with any automobile issue anymore. Nothing is inexpensive to fix any longer!
My son bought the 1500 GMC with the baby diesel this summer. So far so good (he only has 10,000 miles on it ). He does always spout off how great his mileage is, but did mention that is at 65 mph on the highway. Apparently above that it drops off quickly.
Anyhow, sorry to the folks with any automobile issue anymore. Nothing is inexpensive to fix any longer!
dan.kirkpatrick
Well-known member
you might want to stick with what you have//duramaxes have been having crank breakage issues and there are plenty of issues with the 10 speed tranny too,,id be scared of both issues,,check you tube on issues.both very spendy to fix,,plus the cp4 injector pump issues too.
I wouldn't trade it for the world because this truck is my baby and I saved for a considerable time with a paid off 1500, but im curious if its the gas engine or the at4x lift and more aggressive tires bringing me down? 11 is average for city driving the 5-10 miles back and forth to work. The 16 on the screen was a 15 mile stretch stuck behind someone going slow (50ish) so instead of passing I wanted to test how good of mileage I could get. Probably couldn't realistically get it much higher, even downhill, with a tailwind.
2025 with just over 6k and after its first oil change.
2025 with just over 6k and after its first oil change.
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MtsPSU
Active member
Sharp truck!
mevertsen
Well-known member
Seems about right for a 3/4 ton gas truck.
noharleyyet
Well-known member
Great looking truck & runs on 87.
Great mileage and full size 3/4 ton four wheel drive trucks doesn't happen. Nice rig. mtmuleyThatwas key
I have the same truck. Curious, did you notice anything different in regards to your DEF use before or once the warning light came on?
There’s a bulletin out for a software update that is specifically for the DEF system. It is a major update that makes a difference. GMC will not notify you if you need it generally. You have to ask. Just sharing my experience.
I too am very happy with my truck!
My truck’s issue isn’t DEF related. It’s the valve body on the transmission, a whole other GM issue.
I haven’t had any DEF issues with my truck. I’ll ask the dealer if my system is up to date on DEF software updates. Thanks for the info!
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Bonasababy
Well-known member
- Joined
- May 16, 2024
- Messages
- 1,153
Toppers cost a mile or two per gallon in every truck I have owned.
Bought my 25 baby Duramax after a lot of research. Bugs generally worked out in that engine combo now....early babys had more trouble. Long warranty and it was actually cheaper than either gas V8 helped convince me.
With summer blend towing my 18 foot boat I get 19 to 20, unloaded 26 to 28 highway depending on speed...with a mid high topper on it. No doubt would do a few mpg better without the topper.
It's a 1/2 ton LTZ w/Z71 short bed (Gms have the longest short bed) , tow rating 9k and something. Without the off road and with max towing they tow over 11k I believe. Not quite as quick as the hemi Ram it replaced but quick enough, esp. in the passing speed bands.
Doesn't use much DEF, but I don't tow that often. Very happy with it so far.
Bought my 25 baby Duramax after a lot of research. Bugs generally worked out in that engine combo now....early babys had more trouble. Long warranty and it was actually cheaper than either gas V8 helped convince me.
With summer blend towing my 18 foot boat I get 19 to 20, unloaded 26 to 28 highway depending on speed...with a mid high topper on it. No doubt would do a few mpg better without the topper.
It's a 1/2 ton LTZ w/Z71 short bed (Gms have the longest short bed) , tow rating 9k and something. Without the off road and with max towing they tow over 11k I believe. Not quite as quick as the hemi Ram it replaced but quick enough, esp. in the passing speed bands.
Doesn't use much DEF, but I don't tow that often. Very happy with it so far.
