Cylinder deactivation?

There have been issues with its implementation in the past across various manufactures. Honda and their 3.5L V-6 comes to mind. Not sure what the deal is with Ford's implementation but people in general don't like change - especially when it seems to fix something that did not seem broken.
 
What is wrong with cylinder deactivation. I have yet to owned a car with it but in the 2021 F150 Coyote change threads, many people dont like that change. Why? The only problem I hear is Hemi engines cam wiping out. My brothers 2019 Ram has it and I cant tell when it's doing it.
I hated it in my 2009 Challenger RT
Was like very bad turbo lag and ruined the driving dynamics so much I dumped it after 3000 miles
 
All of these schemes to give better mileage, whether cyl deact or stop 'n go IMO they all put undue stress on the motor & its parts. It may be OK in the short term, but not in the long term.

All of these schemes give MINIMAL improvements in mileage...that's part of the problem. I'd rather give up the 0.5-1mpg for longevity.
 
My father's 2013 Grand Cherokee 5.7L has it, and after 160k miles it still isn't very noticeable, and no problems yet. It is turned off when in tow/haul mode. I think with some manufacturers there have been issues (GM 5.3L and Honda's 3.5L VCM come to mind) and it can cause fuel dilution. Also it's another added complexity that can cause issues or be expensive to fix, for what is in most cases a very minimal mpg gain.
 
My Accord has ( had) it, but has been disabled since 29k miles with a vcm disabling device. It was known to cause tons of oil burning problems, spark plug fouling, vibration, drivability issues, as well as broken motor mounts.

I’ve noticed no change in mpg with it disabled and the car is so much better to drive without vcm
 
Cadillac had that V8 in the late 70's that went from 8 to 6 and sometimes 4. What a piece of garbage. I guess the idea was have it running only on 4 for the highway. Fords new all electric Mustang coming out soon and the F150 all electric option coming out in 2022 will change the world.
 
I disable it every time I put my (work truck) 2018 Ram 5.7 into gear by using the +/- gear selector on the shift column. 6 cyl mode is not noticable, but 4 cyl mode has an annoying rumbling vibration. I would permanently turn off the 4 cyl mode if I could, and leave the 6 cyl mode on as it is transparent.
 
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All of these schemes give MINIMAL improvements in mileage...that's part of the problem. I'd rather give up the 0.5-1mpg for longevity.
Be careful saying that around here, you could start a flame war. After all many believe every new technology that hits the mainstream auto world is proven, tested tried and true, 100% reliable, won't leave you stranded, won't cost much to fix after warranty if it does fail, and doesn't compromise engine longevity one bit. Saying otherwise can get you into hot water. LOL

FTR I agree 100% with you.
 
Bought a 2018 Silverado hoping it would work and be a good thing, turned out not so much. Truck seemed confused at speeds between 30-50, as the thing shifted in and out of V8 mode, with the transmission seemingly utterly confused throughout the whole “process”. Developed a check engine light at 35,000 miles (misfire), then a torque converter shudder at 40,000 miles. Oil consumption since day one. Go to the Chevy forums and yup...transmission failures due to the back and forth shifting/accommodating V4 mode, collapsed lifters and oil consumption. Traded the truck in at 50,000 miles.

Wanted to like it...liked the fuel economy...didn’t like my $40,000 dollar truck feeling like it was going to grenade a transmission or drop a lifter at 50,000 miles. Well maintained, babied...couldn’t handle driving up simple hills on the highway.
 
I’ve never heard of this issue so I don’t know. Must be something really new.

Chevy came out with it in 2007, Chrylser in 2006, not exactly new tech. Wait, you're an auto mechanic?

The problem with it is the added parts can fail. The first gens were troublesome, second gens better, Chevy is on the 3rd gen of it.
 
Be careful saying that around here, you could start a flame war. After all many believe every new technology that hits the mainstream auto world is proven, tested tried and true, 100% reliable, won't leave you stranded, won't cost much to fix after warranty if it does fail, and doesn't compromise engine longevity one bit. Saying otherwise can get you into hot water. LOL

FTR I agree 100% with you.
:ROFLMAO:

Very true that there are those who think this, but it's also foolish to blindly believe anything to be 100% reliable.

I'm relatively young (30), work in the IT field, and still feel that while technology certainly has it's place, it should not be integrated where it isn't necessary. Why? Because I fix technology on a daily basis. The software programmers/engineers should take into account that just because you can, doesn't always mean you should.
 
:ROFLMAO:

Very true that there are those who think this, but it's also foolish to blindly believe anything to be 100% reliable.

I'm relatively young (30), work in the IT field, and still feel that while technology certainly has it's place, it should not be integrated where it isn't necessary. Why? Because I fix technology on a daily basis. The software programmers/engineers should take into account that just because you can, doesn't always mean you should.
I agree. FTR there was some my sarcasm,[ the 100% reliable comment] but I really believe there are some people that think this tech is fool proof, doesn't add much cost, will last the life of the car, and is very reliable and dependable. I love technology, I'm not a fan of all of it. Cylinder deactivation is something I'd shut off along with stop start on the dealers lot before I drove home. If there is no way to do that built into the vehicle, then I'd go to the aftermarket for a way to disable it. If that doesn't exist I'd pass on the vehicle. Flame suit back on.
 
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Chevy came out with it in 2007, Chrylser in 2006, not exactly new tech. Wait, you're an auto mechanic?

The problem with it is the added parts can fail. The first gens were troublesome, second gens better, Chevy is on the 3rd gen of it.
I’m not too familiar with Chevy or Chrysler lol I was a dealership mechanic at Toyota. But I’ve worked on most brands but never heard or dealt with this.
 
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