Lugging even with computer control?

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I've been driving this 2017 Sonata company car. It's a basic 4 cylinder GDI rental model.

My question is when driving in a smooth manner trying to get good fuel mileage you can lug the engine at 1,100 rpm by just gently accelerating. There's no down shift and you can hear and feel the engine lugging. I thought with computer control and a 6-speed automatic transmission this would not happen.
 
You'd really need to be seeing what the software is doing REAL TIME on a monitor before coming to any conclusions.
 
Well of course it lugs it. That minimizes rotational losses and maximizes fuel economy. Thats why LSPI is the talked about thing these days; from running these engines hard at a low RPM.
I realize this isnt a turbo car, but they are still going to run it as low as they can get away with.
 
Originally Posted By: Colt45ws
Well of course it lugs it. That minimizes rotational losses and maximizes fuel economy. Thats why LSPI is the talked about thing these days; from running these engines hard at a low RPM.
I realize this isnt a turbo car, but they are still going to run it as low as they can get away with.


Same with my baby Duramax Colorado...can even hear knock on light throttle up in town settings.
 
Are you the only one to drive it? The adaptive transmission might be shifting just right for the last person who drove it, but it will need time to learn your habits.
 
Originally Posted By: OneEyeJack
I've been driving this 2017 Sonata company car. It's a basic 4 cylinder GDI rental model.

My question is when driving in a smooth manner trying to get good fuel mileage you can lug the engine at 1,100 rpm by just gently accelerating. There's no down shift and you can hear and feel the engine lugging. I thought with computer control and a 6-speed automatic transmission this would not happen.


That was always my complaint with high revving engines that lacked torque, and programming to get max mpgs. Too many gears and not enough power to properly utilize it. I bet its probably in 4th or 5th gear at 1,100 rpm and you have to step on it harder to force it to drop a gear, or two. Try a 9 speed mated to a 4 cylinder and you'll really go nuts.
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The lugging can't be good for the engine either.
 
You poor fellows would probably shriek as my sig car putts around town turning corners and lugging out in 4th gear at 900 rpm.

There is no way this can hurt any modern engine...
 
2015 Ford Fusion fleet model company car does same thing when shifter is in normal D position. Putting it in S for sport stops the lugging. But in D it will lug right down to a where you can feel the car start to shudder and will stay there unless you let off or tip in some more throttle to get it to release or downshift.
 
This situation happens more often with a cvt transmission in my experience. They want to keep the engine rpms at a efficient speed.
 
Originally Posted By: Ethan1
Are you the only one to drive it? The adaptive transmission might be shifting just right for the last person who drove it, but it will need time to learn your habits.


I agree with this. When I first got my Camry, it was full of pep and I enjoyed the extra power it had compared to the Corolla I was driving. My driving style calmed down and I noticed the lugging. It got real lazy and was in too high of gear and unresponsive at 1500 rpm. Since driving a little more spirited, the lugging has gone away.
 
I don't mind the low-rpm pull in the wife's crv at all. To truly 'Lug' as one can in a manual, you've also got to be putting in enough throttle input to stress it. In the autos, significant throttle command inspires a downshift. The lower-power lower rpm use, I actually find nice, makes it behave as if it is torquey. maybe it is. As long as the internals are adequately sized, it's just the sensation of vibration to me. I wouldn't worry about it.

good luck,
-m
 
Originally Posted By: SteveSRT8
You poor fellows would probably shriek as my sig car putts around town turning corners and lugging out in 4th gear at 900 rpm.

There is no way this can hurt any modern engine...


Not sure what vehicle you're referring to. If it's the Hemi RAM with the 8 speed ZF, that certainly has the power to properly utilize all those gears.
 
Our 2017 2.3 Eco Boost Explorer in the 45-50 mph range is running at around 1300-1400 rpm at steady throttle. It doesn't appear to lug and a slight tip in on the throttle will increase the rpm's quickly. I'm used to driving manual transmission 4 cylinder vehicles and it just seems like low rpm's. But since this a computer controlled automatic vs a manual I just have to get use to it
smile.gif
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Whimsey
 
As was mentioned earlier, this seems to be intentional programming to maximize fuel economy. Wife's Q5 with 8-speed trans behaves similarly in D. It'll run at 1,200 rpm in 8th, and will not upshift unless you give the gas pedal a big push. I don't like how the engine sounds/feels accelerating at such low RPMs. You can feel slightly more vibration/noise. I suppose most people wouldn't notice, but I do. That is why I typically keep it in "S" mode when I drive it.
 
Originally Posted By: Colt45ws
Well of course it lugs it. That minimizes rotational losses and maximizes fuel economy. Thats why LSPI is the talked about thing these days; from running these engines hard at a low RPM.
I realize this isnt a turbo car, but they are still going to run it as low as they can get away with.


Yep
 
Same goes for my F150. I drive fairly gentle and it up shifts quickly and at low rpm. When rolling through a town at 45mph, it will stay in top gear and loaf at about 950 rpm and with a gentle tip in, will easily accelerate without dropping a gear. It's super smooth and nets me good mpg (for what it is).
 
Originally Posted By: SteveSRT8
You poor fellows would probably shriek as my sig car putts around town turning corners and lugging out in 4th gear at 900 rpm.

There is no way this can hurt any modern engine...


They would passout in the WS6 heading down the highway in 6th gear going just over 60 at like 1380 RPMS and then not even downshifting to go up a 7 percent grade.
smile.gif
 
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