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My Gmc Is A Dog

akkeith

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akkeith Enthusiast

akkeith

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Why is my 09 Sierra 2500HD 6.0L such a dog? When I go to pass another vehicle first there's a pause then it has no acceleration. When it reaches higher RPM's it acts like its got some power but when I punch it going 55mph it acts like I have a six cylinder. My 04 2500 was quick off the accelerator and pushed you back in the seat. Is this something from the factory? Can I do something about it? Thanks for any help.

txab Senior Enthusiast

txab

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Why is my 09 Sierra 2500HD 6.0L such a dog? When I go to pass another vehicle first there's a pause then it has no acceleration. When it reaches higher RPM's it acts like its got some power but when I punch it going 55mph it acts like I have a six cylinder. My 04 2500 was quick off the accelerator and pushed you back in the seat. Is this something from the factory? Can I do something about it? Thanks for any help.

 

Yes and yes.

 

 

http://www.blackbearperformance.com/

Stevens03 Senior Enthusiast

Stevens03

Posted
Posted

I'd have the dealership take a quick look at it, but most likely its the GM nannies built in. It's called Torque Management and can be programed out by Blackbear or another custom tuner. You should have plenty of power to stand up and go... after the nannies let go.. :loser:

akkeith Enthusiast

akkeith

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Why do they do that? You would think they would want the best performance right from the factory. Any warranty problems with performance tunes? Thanks

txab Senior Enthusiast

txab

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It would be a good idea for the dealer to take a look at it just to make sure there is nothing causing this problem other than GM programming. My money is on TM and other designed in nannies.

pm26 Senior Enthusiast

pm26

Posted
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Why do they do that? You would think they would want the best performance right from the factory. Any warranty problems with performance tunes? Thanks

 

They do it because they give you a 100k power train warranty. Aggressive torque management programming prevents sudden loading of the power train and reduces stresses on the driveline and transmission, as well as axles in general.

 

Your 100k warranty may be null and void if you get a custom tune and a major component in the powertrain breaks.

Mike2500HD Enthusiast

Mike2500HD

Posted
Posted
Why is my 09 Sierra 2500HD 6.0L such a dog? When I go to pass another vehicle first there's a pause then it has no acceleration. When it reaches higher RPM's it acts like its got some power but when I punch it going 55mph it acts like I have a six cylinder. My 04 2500 was quick off the accelerator and pushed you back in the seat. Is this something from the factory? Can I do something about it? Thanks for any help.

 

My '07 feels like a dog if I let the tranny program decide when I need a downshift. It wont downshift when it should and then ends up dropping 2 gears and taking off. I started to tap it into tow haul mode when I want it to downshift. Works fine. costs nothing. Im sure the custom tune works better but this works fine for me. The engine runs great. at 3500 rpm it really comes on like a bear. sounds great. Problem is the tranny program tries to keep it at 1500 or less all the time. where theres no power. So it upshifts as quik as it can even though its keeping the engine out of the power band. At times when pulling from a stop up a hill, my truck will upshift until its lugging so hard its actually loosing speed! and still wont downshift. Or when running 50 or so into a hill... Im giving it more gas and its loosing speed and rpm..still wont downshift..down to 1000 rpm...Im down to 40 and it won't downshift...Then wham it dropps 2 gears and races up to 60 before upshifting and lugging itself back down all over again..The engine tourqe and HP carachteristics are not well matched by the tranny program in the interest of meeting government fuel economy and polution B.S.. Fast and easy solution is to tap it into tow haul mode. lay of the throttle a bit and tap it in and she will drop a gear without much unnessisary fuel consumtion and its much more gratifying to drive. Then when the load is past tap it back up and take advantage of the fuel economy program.

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