General Motors has initiated a Service Update for the 2024 GMC Sierra HD, addressing an issue with the 6.6L V8 L5P turbodiesel Duramax engine. According to the update, affected units may not illuminate a Check Engine Light in certain conditions. It’s unclear exactly how many units are affected, however, the same issue is present in certain units of the 2024 Chevy Silverado HD as well.
The Service Update is tagged as N242438501, and was released earlier this month. The update applies to both the GMC Sierra 2500 HD and 3500 HD models, but only those produced for the 2024 model year, and only those units equipped with the 6.6L V8 L5P turbodiesel Duramax diesel engine.
The issue is related to the engine control module (ECM) software, which, in affected vehicles, may fail to accurately diagnose or might not set diagnostic trouble codes when the Selective Catalyst Reduction (SCR or NOx) catalyst is not functioning properly in certain conditions.
To remedy the issue, GM is instructing dealers to reprogram the vehicle ECM and the Transmission Control Module (TCM). The repair involves no replacement parts, indicating that the fix is purely software-related, requiring only reprogramming of the ECM and TCM by dealerships. For owners, this should be a relatively straightforward process with no cost involved.
As a reminder, the GMC Sierra HD’s 6.6L V8 L5P turbodiesel Duramax diesel engine is rated at 470 horsepower at 2,800 rpm and 975 pound-feet of torque at 1,600 rpm. The GMC Sierra HD is also offered with the 6.6L V8 L8T gasoline engine, although this Service Update does not apply to the gasoline powerplant. Output is sent to the wheels via the GM 10-speed automatic transmission, with both rear-wheel drive and four-wheel drive offered. Under the body panels, the 2024 GMC Sierra HD rides on a more capable variant of the GM T1 platform. Vehicle production takes place at the GM Flint plant in Michigan.
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Comments
How about a van based on the Colorado platform with a LWB version?
How about an S10 Blazer size SUV based the Colorado? The van would be cool to.