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Discussion Starter #1
My l5p 2019 27k miles l5p when slowing down and there is no load on engine or the wheels pushing it around 1k or whatever rpm surges around 200rpm. Like the tach bounces like it cannot regulate speed well under no load conditions. Has anyone else experienced this? Just curious. Doesn’t hurt anything but seems off for a 70k dollar truck ...

Thx!


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I have a '19 and it does the exact same thing. It's usually when I am coasting to a stop, under little or no load. I live on a hill and leaving the house I always coast down the street to a stop sign and the engine "chugs" or "bounces" to a stop. Interestingly, although it can jump up in rpm's it doesn't cause any surge in the drivetrain, I still coast. I have only had it put power into the drivetrain a couple of times and both times I was going up a slight incline coasting to a stop.

The truck has 10k and has done it since day one. I plan on scheduling a visit with the dealer but wanted to get a few miles on the truck to see if if would resolve itself - it hasn't.
 

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Discussion Starter #4
I have a '19 and it does the exact same thing. It's usually when I am coasting to a stop, under little or no load. I live on a hill and leaving the house I always coast down the street to a stop sign and the engine "chugs" or "bounces" to a stop. Interestingly, although it can jump up in rpm's it doesn't cause any surge in the drivetrain, I still coast. I have only had it put power into the drivetrain a couple of times and both times I was going up a slight incline coasting to a stop.



The truck has 10k and has done it since day one. I plan on scheduling a visit with the dealer but wanted to get a few miles on the truck to see if if would resolve itself - it hasn't.


No rough shift not talking about that. Any tranny will do that depending on conditions.

Yes. Exact as you say. It isn’t enough surge because of gear it’s in and rpm increase isn’t enough to influence drivetrain which is good. Strange tho. If you find a resolution or software update please let me and the readers know!!


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Is the bump when the trans does a downshift?


Isn’t really downshift no. If anything it does it in opposite scenario. Like too high a gear and rpm is low. Noticed it was around 800rpm it did it. But it’s small enough doesn’t make torque go to wheels generally.


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No rough shift not talking about that. Any tranny will do that depending on conditions.

Yes. Exact as you say. It isn’t enough surge because of gear it’s in and rpm increase isn’t enough to influence drivetrain which is good. Strange tho. If you find a resolution or software update please let me and the readers know!!


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I plan on scheduling a visit the first of the new year. I love the truck, coming from a '16 LML. I only have three issues.

1. The engine chugging
2. The transmission shifting is often abrupt and "searching"
3. There seems to be some type of driveline slack or drop coming off a full stop - it's intermittent. Like the driveline is loading up and then releasing - a clunk feel.

Funny, my '16 had a really smooth trans, it shifted predictably. This one not so much.

All of these issues are, (or seem to be), not major. Hopefully I'll have a good report for you guys!
 

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I have a '19 and it does the exact same thing. It's usually when I am coasting to a stop, under little or no load. I live on a hill and leaving the house I always coast down the street to a stop sign and the engine "chugs" or "bounces" to a stop. Interestingly, although it can jump up in rpm's it doesn't cause any surge in the drivetrain, I still coast. I have only had it put power into the drivetrain a couple of times and both times I was going up a slight incline coasting to a stop.



The truck has 10k and has done it since day one. I plan on scheduling a visit with the dealer but wanted to get a few miles on the truck to see if if would resolve itself - it hasn't.
That's interesting that 19 models are still doing that. Me and brother had 17 models and they both did the same thing basically.

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Discussion Starter #8
I plan on scheduling a visit the first of the new year. I love the truck, coming from a '16 LML. I only have three issues.



1. The engine chugging

2. The transmission shifting is often abrupt and "searching"

3. There seems to be some type of driveline slack or drop coming off a full stop - it's intermittent. Like the driveline is loading up and then releasing - a clunk feel.



Funny, my '16 had a really smooth trans, it shifted predictably. This one not so much.



All of these issues are, (or seem to be), not major. Hopefully I'll have a good report for you guys!


Interesting. I don’t think I experience those issues shifts pretty good. But I baby it and mostly highway.

I’m not exactly sure what chugging is but don’t think it does?


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