New 6.6 Liter Engine in GMC Trucks?

fwcer

New member
Beginning with the 2020 models, gas powered GMC one-ton trucks will have a new engine, a 6.6 Liter V-8.

Have there been any problems/complaints regarding this new engine?

I am thinking of getting a 2020 Sierra, but I am wary of buying any vehicle with new, untested engines.
 

Buddha.

Lurker
The new 6.6l in GM trucks is just a bigger(and detuned) version of the 6.2 liter they've been making for years. I wouldn't expect the 6.6 to have any problems the 6.2 isn't having. Probably less prone to problems since it's only offered in HD trucks and therfore it doesn't have displacement on demand.
 

phsycle

Adventurer
I thought the 6.6L was just coming out in the heavy duty trucks? I assumed the OP was speaking of the 2020 HD's. But, same applies. Could look at a 2019 HD.
Correct, he was talking about the 2020 HD's. I was talking about the 2019 Sierra HD. If he doesn't want a first year production engine, I don't know why he would be looking at getting a first year engine. Just get the current year. :)
 

phsycle

Adventurer
Correct as far as I know. I thought the 6.2 was / is a 1500 series engine and the 6.6L was replacing the 6.0L in the HD trucks.
Ah, ok. Well, the 6.0 then! :)

I don't know my GMC trucks that well. Never been interested in them. Although just the other day, I was looking at some 12-13 Avalanches. Those were pretty cool trucks.
 
Ah, ok. Well, the 6.0 then! :)

I don't know my GMC trucks that well. Never been interested in them. Although just the other day, I was looking at some 12-13 Avalanches. Those were pretty cool trucks.
They were! Essentially the same trucks as the Suburbans I've owned. They were okay. No worse or better than any other make of truck I owned. I think nowadays they're all pretty good.
 
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fwcer

New member
Then why don't you just get a 2019 Sierra with the 6.2, then?
I spoke to a GMC sales agent today, and he says the factory stopped making the 2019 model several months ago. He says the 2019s are hard to find in the dealers' lots at the present time.
 

zoomad75

Observer
6.6 is HD only. Essentially using the same technology found in the DI 5.3 and and 6.2 light duty engines. I don't expect any issues as the light duty engines have been in use since 2014 in the trucks. I wouldn't stress on the engine being it's first year.
 
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