General Motors created a buzz when they released a small block inline 6 3.0-liter Duramax diesel for a variety of trucks and SUVs like the 2020 Chevy Silverado 1500 and newly updated 2021 Chevy Tahoe. However, there is a big detail prospective buyers need to know about this engine.
Officially, this engine is also found in the 2020 GMC Sierra 1500, 2021 GMC Yukon and 2021 Chevy Suburban. Although, it is absent in both the off-road versions of GM’s full-size SUVs (more on that in another story).
The engine is a ground up design made to fit perfectly in those vehicles and produces 277 horsepower and 460 pound-feet of torque in the half-ton Silverado with a surprising peak torque at just 1,500 RPMs.
It also includes a variety of innovative engine technologies like ceramic glow plugs that heat up faster providing a quicker cold start, a lightweight aluminum block, low pressure EGR and a variable geometry turbocharger.
That’s a lot of fancy words to say the inherently balanced inline-6 is the leading edge of new diesel engine technology. However, there is that one thing.
What is that one thing? As soon as the news of the engine hit the internet, people quickly pointed to an oil pump belt residing in oil and needing to be inspected at 150,000 miles. While the belt sitting in oil is a bit concerning to many, the fact it is a belt, not a chain or gear driven, also drew some concern. Yet, the MOST concerning part of the belt is the fact you have to drop the transmission to service the belt. Yes, that’s not a typo. You have to drop the transmission to be able to access the belt to INSPECT it at 150,000 miles. This has drawn a lot of criticism.
We received so much feedback on this concern, we reached out to GM to interview their engineer on this engine. This engineer has been with this engine since its creation and spoke to us at length about why the belt was chosen and why, yes, it is true, the transmission has to be removed to access the belt.
Check out our video interview below:
The bottom line
While yes, removing the transmission to inspect a belt is rather ridiculous, and you are looking at around $1,000 for a mechanic to do the inspection, we are talking about a one-time inspection at 150,000 miles. We agree, we don’t like it anymore than you do, but the driving experience from the diesel outweighs the hassle in our opinion. Plus, the fuel economy in the Silverado 1500 approaching an unheard of 30 MPGs is crazy good.
GM tells us they are looking closer at this belt and will be seeing what they can do to redesign or change out the belt for something else. If they do, we will let you know. For now, just be aware as you are shopping what you are getting into.