Hey everyone. I have a 2011 LML with 36k miles. A few days ago I just did EGR/DEF/DPF deletes along with new downpipe and 5" flo pro. I flashed my new tunes and I love everything about the truck except I don't think something is quite right. If I mash the accelerator in first gear and I lose traction, the truck will hit the rev limiter and when it does it's like it hits a brick wall and falls flat on its face. It quits making any power for what feels like a full second. It doesn't just hit the rev limiter and keep bouncing off of it, it just feels like it shuts down for a second.
I am only running the 60hp Tow tune and my fuel filter life still has a percentage so I don't think I'm draining the rails....
Does it do it in every gear, sounds like shift defuel and if that's what it is then it is normal. Is it actually hitting the rev limiter or just feels like its falling on its face on every shift
What exactly do you mean by this? Are you stating that because you are above 0% remaining you're fuel filter is still okay? I've never run my "Fuel Filter Life Remaining" below 65%. Running that meter out before replacing the fuel filter in these trucks is simply too long. I agree with the gents above though. Sounds like you haven't taken TC/ST off. If you fill out your sig people will have a better idea what you're running. Makes it easier for us to help you.
I do have the traction control and stabilitrack shut off.
What I meant by the fuel filter percentage is that it is still showing a percentage of life left. I thought that when guys were draining their rails the fuel filter life dropped to zero or something... Also, what I listed in my original post is what I have done to my truck.... No more, no less. That's the reason I put it in my orginal post.
2011 Silverado 2500HD
5" flo pro straight pipe
3" Profab downpipe
EGR delete kit with modified up pipe
Kory Willis 60 HP Tow Tune
When these trucks hit the "limiter" they just defuel and stop accelerating. They don't bounce off of it like a gas motor. Not quite sure of your problem. Could be trying to defuel to shift, could be losing rail pressure. If you have a monitor that can see rail pressure that would help diagnose it.
The truck doesn't do it every shift, it does it in first gear and if you lose traction and the tires spin, the rpms go up and it hits the rev limiter, at 3600 rpms, then even if you keep your foot in it, it just shuts down all power for about a full second and it wont pick back up again until the rpms fall to about 2k rpms.
The scenario I first noticed it was I was at a stop light and I was going to turn to the right and lay rubber. All went well until the truck hit 3600 rpms, where it hit the rev limiter and quit making any power. Due to the instant loss of power there was a big pop that sounded like a carb backfiring, I'm assuming this was a loud turbo bark.
My truck sounds just like this gentleman's truck when it happens. He posted here last October asking about a backfire. He never posted if he got his issue resolved or not.
When you watch the video, imagine that you mash the accelerator when he does and you don't ever let off of it... That is what my truck does. At 6 seconds in the video when it sounds like he let off, I guarantee you he still had the pedal all the way down. Its like it shuts off, or defuels or whatever you wanna call it and then it doesn't pick back up for a second until the rpms drop considerably.
Don't rev your truck up to 3600 its going to break something. That kind of rpm is getting into the built motor territory. No wonder you are having weird issues, I can see 3600 rpm with the mph to match but that much rpm with a tire spinning around a corner... That's no bueno
That's all fine and dandy but I should be able to do a burnout or whatever I wish in my vehicle. It should be shifting in second and still spinning the tires, not just hitting a rev limiter and dying...
I have experienced the same thing in my truck and also other cars and trucks i have had over years. From what I understand its just the truck defueling and also massive torque management kicks in and pulls timing etc to try and keep things from breaking. I am sure PPEI tunes have the torque management jacked up even more then factory to prevent guys from going balls out with the extra power from blowing crap up. Its a safety buffer.
Take traction control off and see how it is. I betcha itll still do the same thing but much less drastic because taking the traction control off will reduce torque management from like 80% probably down to 20%.
I really wouldnt worry about it too much. If you want to spin the tires just take off TC. Torque Management is the like government holding you back lol. !
This was my first issues when i first reflashed . tranny was doing all kinds of weird stuff. over revving, over shifting, lazy shifts etc. then when i remembered tranny has to relearn i tried driving more consistent and tranny seems to be getting better and better but is taking time. My issue is too that its all icey and snowey out so hard to due consistent pulls. :drink
Basically best advise just drive it and try to let it go through gears at different throttle positions and it should get better and better.
All of this is with the TC and Stabilitrak off. I did let the tranny do about 100 miles worth of city driving learning. Its just weird to me that at worst it wouldn't just "bounce" off of the rev limiter instead of completely shutting off. I've seen videos of diesels bouncing off the rev limiter before and while its not something that I want to personally do to my vehicle, I would rather it bounce off the rev limiter than just completely shut off...
Did deletes on my truck about 1 week or 2 ago. Flashed 60 HP ppei tow tune. When first driving tranny was shifting all erratic . some shifts soft, some hard, over revving past 3/4 throttle. All over the place. Scared me thinking my tranny was going yet just changed fluid 4 weeks ago over to transynd and fluid was barely dirty. Truck shifted beautiful before deletes.
So fast forward 2 weeks. Just took my truck out for little rip literally 1/2 hour ago. Did some more runs from stop 1/2 throttle holding pedal up to 60-70 letting it shift. Then did 3/4 throttle. All shifts pretty good. So I said OK let's see what wot does this time . matted to floor from a stop every shift hit perfect and firm. So long story short trans just needed prob 100-200 miles of different driving to finally relearn everything . so my recommendation from experience just keep driving it and trying to do long runs letting it shift through as many gears as you can while holding pedal steady. Do 1/4 throttle , 3/8, 1/2 etc. Once they all feel good go to WOT and betcha all will be just fine !
^ ^^^
What he said. I don't think you have a problem to be honest. If your tires are spinning in bad driving conditions you should be able to shut it down long before it hits the rev limiter. In all likeliness it's probably a good thing it doesn't "bounce" off the rev limiter. The GM engineers probably figured that this is the best thing for the truck. The noise you heard was likely your transmission clunking or something along that line. You were hitting the rev limiter in slippery conditions half way through a trans. realearn. I'm sure all kinds of funky things were happening in there.
I will definitely keep driving and hopefully it does learn and get better.
I just want to clarify something... I drive like a grandma about 99% of the time. My reason for wanting to do tune and deletes was only to rid the truck of emissions crap. I could really care less about more horsepower. After doing all the work and driving for a while I figured, screw it...I'm gonna have a little fun. I spun the tires one time around a corner and this is where I encountered my "problem". Since then, I haven't been trying to do big smoky burnouts or anything, I've just tried replicating the "problem" again which I have. I see all these youtube videos of trucks just like mine doing big badass burnouts and that's all cool, but I don't do stuff like that. However, its just odd to me that I watch all these videos and and I don't hear trucks having trouble shifting into second and hitting the rev limiter or shutting down like mine. Just my 2 cents....
Mines all good now. Just getting this p204 code every once in a while. I clear it and then its back few days later sometimes. Pressure switch code. Weird
My 2011 de fuels really hard like your describing on 1-2 & 2-3 shifts it almost feels like it kicks into neutral when it does it, it just stops pulling till the shift is complete. I'm blocked w/full exhaust & mbrp DP. Did the trans relearn twice and it still does it just not as bad, the Allison won't let you hurt it so there is a lot harder of a de fuel with all the extra power after the tunes. Oh and no codes, been tuned for about 15k. Beat on her occasionally with 37s, no issues so far thankfully
What tune are you set on? I am running PPEI's 60 hp tune with no lift pump and the only time i feel defuel is when I break the tires loose launching hard from a stop in 2WD. Even with the stabilitrack and TC off the computer takes over and stops my stupidity. The LML doesn't like immediate throttle opening but more gradual throttle opening. Mess around with it and you will see the difference, try passing by dropping the hammer and then by easing into it and you'll see what works best.
His signature
"2011 Silverado 2500 HD 6.6 Duramax (LML)
-Kory Willis Tunes
-Fully Deleted
-Deviant EGR Delete Kit
-Flo Pro 5" Straight Pipe Exhaust- No Muffler
-ProFab 3" Downpipe
-ProFab Modified Up-pipe"
showed that he doesnt have a lift pump.. could it be draining the rails?
Any updates on this from anyone? I have a 2012 with korys tunes, I daily on the street tune and get the same thing. Light the tires up and the truck hits rev limiter and falls on its face. Traction control and stabilitrac are turned off, I have tried manually shifting as well as leaving it in drive. Tow haul mode on or off doesn't matter. The truck just falls straight on its face trying to do a burnout. I'm not saying that I wanna go terrorize the streets but you should be able to let the tires rip every once in awhile!
I think you need to back off the pedal a little before the limiter hits and let it shift to second gear then get back into it to increase Tire spin. Not really a good idea but everybody likes a little fun
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