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Discussion Starter #1
So, I'm joining an on-ramp and I punch the gas. The truck shifts down as I'd expect (it's an automatic of course) but then it immediately shifts back up again. I lose the acceleration I was building and get a bumpy ride. Is this the 'dreaded torque management' I read about on PCM for less' website?
 

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Im not exactly sure, but the same thing happens to me, really doesnt make sense.
 

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Discussion Starter #3
Glad I'm not the only one! It only happens if I "floor it". Gentle acceleration is no problem and I have no other problems with the truck. The first time I noticed it was when I was going to overtake someone. So there I am driving into oncoming traffic - and losing my passing speed! I'd go as far as to say it is freakin' dangerous.

Anybody know if this can be programmed out?
 

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Ralph2LTZQ8 said:
Glad I'm not the only one! It only happens if I "floor it". Gentle acceleration is no problem and I have no other problems with the truck. The first time I noticed it was when I was going to overtake someone. So there I am driving into oncoming traffic - and losing my passing speed! I'd go as far as to say it is freakin' dangerous.

Anybody know if this can be programmed out?


Absolutely, you are not the only one.



You mean like you hit it, it downshifts, revs up, then when you get the false sense that you can fly by someone, it shifts back down and accelerates, but just not what youd expect? At least thats my expereince, I hate it the most entering on the on ramp like you stated.
 

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Discussion Starter #5
It shifts down, revs up, then for no apparent reason shifts back up and the revs drop down again killing your acceleration. It has to be a computer thing.

It's kind of embarrasing to if you've got passengers who you've just been telling that your truck is so d**m good :oops:
 

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Discussion Starter #7
Actually I got to thinking what MarkEG said because that is also true. I had noticed before that when my foot is hard on the gas and she's pulling hard, it will shift down when I wouldn't expect it to, or wouldn't choose to if I was driving a stick.

School bus drivers call this "see-sawing" I believe. :D

Is anyone from PCMforless watching this thread. Is that the torque management that you speak of?
 

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Ralph2LTZQ8 said:
It shifts down, revs up, then for no apparent reason shifts back up and the revs drop down again killing your acceleration. It has to be a computer thing.

It's kind of embarrasing to if you've got passengers who you've just been telling that your truck is so d**m good :oops:


Yep, thats it.



Im hoping that it can be fixed by a tune.
 

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Discussion Starter #9
Found this in another thread written by a PCMforless employee, his site name on here is [email protected]...

Yes shift firmness is just for an auto trans. You're the only one who can control it if you have a manual. We can raise the rev limiter for you though if that's what you are getting at.

We do change the spark tables as part of the tune. And yes you would want something different for running nitrous.
This really makes me think the stock tune (the 'shift firmness' part) can be modified to eliminate what we're experiencing.

Anyhow, here's the link to the thread. Check it out for yourself. I might just e-mail the guy to see if our hunch is correct.

http://coloradofans.com/forum/viewtopic.php?t=53643
 

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I had TM removed when i did mods on my C6 a6 vette, it was a death trap after TM was removed!

You could be going 20mph then go WOT and the car would take a 90 degree hard left dive, something you don't wanna do with traffic around you.
 

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CHASLS2 said:
I had TM removed when i did mods on my C6 a6 vette, it was a death trap after TM was removed!

You could be going 20mph then go WOT and the car would take a 90 degree hard left dive, something you don't wanna do with traffic around you.


We're dealing with minor HP compared to your vette though :lol:
 

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Discussion Starter #14
I e-mailed [email protected] and included a link to this thread. He didn't get on here yet apparently.

MarkEG - did you check out that 'shift firmness' thread?

So if TC is traction control, what is TM - torque management? CHASLS2, do you think this is some kind of traction control system cutting in? I still have my original window sticker and there is no kind of traction control or torque management listed. Plus I can spin the wheels in low gear, rain or dry, pretty easy. (I get wheel bounce sometimes though!) :oops:
 

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I don't know if my 08 3.7 a4 colly has TM, heck i dont even have a TC Button in my truck.

I have a stripped down base work truck colly.
 

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Discussion Starter #16
My truck is pretty loaded, but no TC button either. I don't even know if Colorado's have the option. Maybe it only comes on the 4x4's? Only GM vehicle I have driven with TC is a Tahoe. It cut in one time taking some bends on an uphill mountain road. I saw the light come on on the panel, but didn't 'feel' anything. This shifting issue with the colorado seems to only happen at a certain speed/throttle position/gear combination.

Gunning the motor hard to get up a short on ramp, or trying to quickly pass another vehicle from average highway speed would be good examples.
 

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Ralph2LTZQ8 said:
I e-mailed [email protected] and included a link to this thread. He didn't get on here yet apparently.

MarkEG - did you check out that 'shift firmness' thread?

So if TC is traction control, what is TM - torque management? CHASLS2, do you think this is some kind of traction control system cutting in? I still have my original window sticker and there is no kind of traction control or torque management listed. Plus I can spin the wheels in low gear, rain or dry, pretty easy. (I get wheel bounce sometimes though!) :oops:
Kelly is a gal.
 

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I don't believe you are experiencing torque management. Torque management should only kick in when you are starting from a stop or the wheels suddenly start spinning.

What happens there is that the PCM cuts the fuel off until the excessive wheel spin or torque is reduced and then begins to fuel again. What you are describing sounds like the PCM can't decide what gear to be in.

Contact the stealership and see if they have an update for your transmission.
 

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Its also possible that my issue is caused from a different rim/tire combination.....but from what I can recall, it was happening even before I changed that up.
 

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It might have been happening before - but it's likely to be worse now.
 
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