GM has issued a voluntary emission recall for the 2024 Chevy Silverado HD and 2024 GMC Sierra HD equipped with the 6.6L V8 L5P turbodiesel Duramax engine, which may have an incorrectly adjusted Electronic Control Module (ECM) leading to improper fuel injector flow.
The problem: the Engine Control Module (ECM) may not properly adjust fuel injector flow for the normal variation in fuel injector flow rate characteristics.
The hazards: incorrect adjustment of the fuel injector flow rate may lead to the Chevy Silverado HD or GMC Sierra HD unit experiencing a rough engine idle as a result. The truck may also consume more diesel fuel than normal while operating, lowering the fuel economy.
The fix: GM instructs dealers to use the diagnostic scan tool to carry out the process of Fuel Injector Flow Rate Programming, which will update the ECM with correct fuel injector flow rate data and resolve the issue. No parts are required for this repair, as it’s carried out entirely through updating of electronic data for the affected system.
Dealer service personnel should check to ensure a specific Chevy Silverado HD or GMC Sierra HD unit is affected by the emission recall before beginning servicing procedures. This can be done by consulting the GM Global Warranty Management system, where affected Silverado and Sierra trucks will be marked “Open” on the Investigate Vehicle History screen.
Affected components: Engine Control Module (ECM).
Affected vehicles:
- 2024 Chevy Silverado 2500HD
- 2024 Chevy Silverado 3500HD
- 2024 GMC Sierra 2500HD
- 2024 GMC Sierra 3500HD
Number of affected vehicles: GM has not provided information on how many Chevy Silverado HD and GMC Sierra HD trucks are affected by this voluntary emission recall.
Owners should: owners who have further questions should contact Chevrolet or GMC customer service at the toll-free telephone numbers provided below, referencing the recall number as necessary.
Contacts:
- GM recall number: N232415860
- Chevy customer service number: 1-800-222-1020
- GMC customer service number: 1-800-462-8782
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Comments
I’ve heard several guys on forums complaining about bad fuel economy on their 24’s. Hopefully this resolves the issue.
I had my 2018 6.8 Totaled and my new 24 6.6 Duramax gets like 4 mpg less. Anyone else noticing this
Yes. My 2017 was a fuel economy rockstar. I foolishly traded ‘up’ to a 24 and it sucks fuel by comparison. At least 4mpg worse average and I’d say closer to 6-8 worse in short trip use. It also loads the dpf super fast. After a fully executed regen, it will be at 70% within 50 miles. Going to the dealer tomorrow because the truck is stuck in a death loop trying to install one of the 3 OTA updates that have come out recently and I’m hoping they tell me I’m included in this recall
yes, traded in my 2019 3500hd dually duramax for 2024 and now getting 4-5 mpg less ,disappointed 2024 10 speed transmission and 3.42 gear ratio , mileage should have improved at least not went down. Dealer said my truck was not recall list , dont know what to do ?? any suggestions ??
I hope the MPG gets figured out. I trading my ’18 for a ’24. Losing 4 is not what I want to hear.
I called my dealer, they said there is no fix yet. If someone actually gets a dealer to fix this, please post the fix here. I too traded an ‘18 that got great fuel economy. I am seeing 10 mpg on short trips , babying it on the highway I am seeing 16 mpg tops. 12-14 is common.
I’m seeing similar lackluster mpg…my ’15 Dmax is tuned, mildly lifted, big tires, heavy bumper…18-19hiway. New ’24 Dmax, bone stock, only 16 hiway. WTH??
I have 8000 miles on mine and it is getting better. First oil change seemed to help at 7000 miles. I went from 15-16 new mpg hwy to 19-20 mpg on the highway now. Granted this is keeping my foot out of it but not babying it. City still not great at 14-15. I didn’t believe all of the “it will get better with break-in” bs, but does seem to be panning out. I came from an ‘18 GMC 2500 that I could regularly get 20-22 mpg on the highway and was considering dumping the ‘24 for horrible mileage.
Same here. Mine is 2023 and fuel mileage and DEF fluid is the same as 2024 Silverado. Terrible… I’m looking at trading it…
I have had a 2007 a 2015 and a 2018 gmc Sierra 2500 hd 6.6 liter diesel.they have all been about the same on fuel mileage.I am one of them people that set back the odometer every tank full.I usually get about 10.5 to 12 mpg pulling my trailers or 15 to 18 around town .on good days long trip I could hit 26mpg on the 25 mile setting.on the other hand my new 2024 has averaged 10.5 mpg on the first 3000 miles ,maybe 10 percent pulling trailers. Now the truck has 6000 miles on it and has been averaging about 11.5 mpg no pulling ,and the best is up to 18 on a straight perfect flat road .yes I’m not happy, thinking 4mpg worse
My 2024 2500WT barely uses any DEF but the mileage stinks! It picked up a little after about 2000 miles – from 14-15 to 16mpg. This is no load – babying it. Mine does have the Max Tow Package with the 12″ 3.42 Axle which could make some difference. I’m just over 4000 miles on it now, have just under a half tank of DEF and haven’t added any since I bought it.
It may be coincidence – but the small mileage increase also coincided with switching from Shell to Exxon Diesel.
I think mine is on the recall list. Has anyone had the recall performed yet and did it help?
My 2024 3500 aT4 seems the same as Ross, I have 5400kms, just did a 300km road trip with no load and flat driving…got 15.9L/100kms, which amounts to 15.6 mpg. This was traveling at 125KMh(77 miles/hour) and I still haven’t put in any DEF. Something needs to be done with this terrible mileage.
I traded my ‘18 duramax for a ‘24 ultimate and lost 6-8 mpg