2019 GM trucks get smarter fuel-saving cylinder deactivation

ShinerBock wrote:
Interesting bit of tech in the new GM V8s to increase fuel economy.

I'll believe it when I see "it", meaning any improvement in fuel mileage and/or performance. :( My 2012 Silvy has fuel management and honestly I see no advantage at all, in fact the truck gets slightly less fuel mileage overall than did my previous 2006 Silvy and 2005 Avalanche, neither of which had any sort of cylinder deactivation system but both of which ran the same 5.3L engine and same 3.42 axle even though they also both had the older wide ratio 4-spd transmission that supposedly wasn't as efficient as the narrow ratio 6-spd I have in my current '12. I see this stuff more as fluff for sales brochures, not an actual on road performance improvement for owners.

BB_TX wrote:
Don't know what the difference is but a good friend's 2017 GMC Denali SUV has that feature. Or at least similar. I think it deactivates two cylinders when cruising at highway speeds and not under any undue load. I can not tell when it changes back and forth when I ride with him.

The difference between this system and the current one your friend has that the new system can deactivate any cylinder at any time depending on load requirements rather than just four cylinders.

Don't know what the difference is but a good friend's 2017 GMC Denali SUV has that feature. Or at least similar. I think it deactivates two cylinders when cruising at highway speeds and not under any undue load. I can not tell when it changes back and forth when I ride with him.

Had a friend that had a ‘80 something Chevy that had “cylinder deactivation”, the problem was....all eight (8) were “deactivated “! :B

it would be interesting how this would work on a diesel. the duramax has way more power and torque than needed in most driving, especially in town. and with direct injection it would be pretty easy to deactivate cylinder(s).

1995brave wrote:
Better than the original try with the Cadillac engines.

Yeah, that was one idea that was way ahead of it's time and did not have the technology to support it. Thankfully computer processing has vastly increased in speed and multitasking since then that it can handle the fraction of a second timing events needed for today's engines.

Better than the original try with the Cadillac engines.