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I wonder if some of this issue is coming from a "rolling" stop? My 2016 Corvette Z06 stays in 3rd until you are nearly stationary at which point it skips 2nd and goes directly into first. If you roll back into the throttle during that shift it gets confused not knowing whether to continue into first, stay in third, or split the difference and choose second.

The only really weird shifting I have gotten with my 2018 Denali is during the first couple of times when it went into regen in stop and go traffic; probably a combination of the different engine parameters used during regen coupled with an Allison still early in its learning mode. The Allison 1000 can live at L5P ratings partly because it uses what Allison calls shift energy management which basically means it calls for a power reduction during shifts and I suspect a rolling stop could confuse that algorithm.

I am sure at some point I will accidentally discover what driving events bring out the dead pedal so I can avoid those conditions. Shortly after I traded my 2001 Duramax in on a new 2006 I had about 600 miles on it and needed to pass on a 2 lane road. The car I was following was going just fast enough that the transmission had shifted into 6th and when I pulled out to pass I got to experience a combination of a heavy duty transmission needing to go to a lower gear along with turbo lag; it was probably only about a second before it responded with plenty of power and speed but looking at oncoming traffic that was a really LONG second :) After that when I needed to pass in a hurry I would manually select a lower range and build up speed and boost before pulling out; so far no complaints about the responsiveness of the 2018 but my daughter always likes to remind me that I am driving a big pickup and not the Z06.
 

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WTF.....I thought the "dead pedal" was an LML only problem.


The reason GM does this is to reduce smoke in order to protect the dpf. Anytime you mash the throttle at low rpms with no boost fuel would normally be dumped which can’t burn efficiently until turbo spools up. I’m sure most of you that have done dpf deletes in past know this from experience. Once the dpf is off aftermarket turners want fast power response thus program the ecm as it should be which is to apply the fuel quickly. That’s why you get the initial surge of black smoke when jumping on the throttle while coasting or at a standstill.

Ford has to do the same but gets away with it a little better with their 6.7 motor design. The overall distance from turbo to inter-cooler to cylinders is much shorter. Due to the shorter distance less time is required to compress air for each cylinder resulting is improved throttle response.

So when some of you are saying the L5P has slower response times are you comparing that to tuned previous engine generations or non-tuned?



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My untuned '06 was consistently quicker to respond than the L5P is. For the short time that I had both of them, I had to be conscious of which I was in so that I either didn't misjudge a gap in traffic or light the tires.
 

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My untuned '06 was consistently quicker to respond than the L5P is. For the short time that I had both of them, I had to be conscious of which I was in so that I either didn't misjudge a gap in traffic or light the tires.


Ok then yes. Any 07 or earlier truck of any brand will have better throttle response. Simple due to pre-dpf exhaust systems.

Actually I’m pretty impressed with my L5P. For a dpf truck it’s actually way more responsive than my 08 F250 was factory.


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I'm going to start charging you every time you mention your Z06.
I have to show it some love because I sure can't drive it with the temperature dropping to well below zero and snow/ice everywhere :) It shares a garage with my Deere utility tractor and I am pretty sure the tractor smirks at what it calls the little blue pansy every time I start the tractor to plow the driveway.
 

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I have to show it some love because I sure can't drive it with the temperature dropping to well below zero and snow/ice everywhere :) It shares a garage with my Deere utility tractor and I am pretty sure the tractor smirks at what it calls the little blue pansy every time I start the tractor to plow the driveway.
No balls!

 

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Well I have had both a 2017 and 2018 L5P. 2017 only issues in 23,000 miles were tuning that would push through normal break pedal pressure (especially in reverse). And now the 18 is in the shop for a water leak that comes from under the steering column. BTW it has just over 12,000 miles on it.



So 35,000 miles in 18 months and only issue thus far has been tuning corrected.
Have they found the cause for the water ? I'm dropping mine off Tuesday for the same water coming in from somewhere

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My LP5 has 40,000 really only stupid things related to tech have given me issues, however if you had the BD throttle enhancer you will be very happy with the acceleration, I took it off to drop at dealer and wow I cant stand riving it now!
 

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I have had similar with my 2015 Z06/Z07. One of the first things I noticed with my 2019 High Country is some strange shifting. I noticed especially in the morning when it was cold.
 

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My LP5 has 40,000 really only stupid things related to tech have given me issues, however if you had the BD throttle enhancer you will be very happy with the acceleration, I took it off to drop at dealer and wow I cant stand riving it now!
The idea of a throttle enhancer had crossed my mind before seeing the Banks Derringer. Good to know you like the BD unit. Also seen Pedal Commander and Vitesse Motorsports show up in web searches I've done.

It'll come down to how my dealer views devices. I've read about others removing the Derringer before taking their truck in and some leave it in without issues.
 

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Have they found the cause for the water ? I'm dropping mine off Tuesday for the same water coming in from somewhere

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Turned out to be the shark fin antenna seal. They had to replace the antenna since the connector on the bottom corroded. from what I have read, its common.
 

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I'd have to say so far(2200 miles) I love the l5p. It looks to be getting better mileage than my previous LMLs. Outside of that, the truck is identical to what I've owned previously. I'll be doing a heavy tow to Colorado for vacation this summer and I'm looking forward to it.
 

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Well I'm glad after reading 18 pages no one has mentioned my issues. At 560 miles DEF Injector went out. Code P10D1. Then at 8,142 miles another CEL for the exhaust particulate sensor replacement. Also had the issue with the low coolant sensor. Not the way I wanted to start out with my first diesel. Love the power and pulls my 39' 5ver effortlessly. Only have 9300 miles on, hope it gets better.

2017 3500 Silverado High Country SRW
 

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I have a 2019 High Country with about 7500 miles on it and so far besides a few recalls I've gotten a code of P20EE and everytime I take it to the dealer they clear the code and tell me nothing is wrong. Other then that I love the damn thing.
 

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I have About 14k on my 17 L5P with about half of that towing a 10k lb trailer. It has been such a great truck with only a few minor programing updates. Mileage is better than i expected. Last trip from northern to sothern California I got 24.2 mpg running empty at around 75 mph.
 
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