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Old 09-26-2025, 04:03 PM   #1
b4wheeler
 
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Drives: 2011 Camaro 2SS Vert
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Hard downshift

I want to ask this here to see if this can be fixed in a tune.

Just had convertor and gears installed in my car.
Had a tune emailed to me.
Car runs great.

One little issue.
When in manual mode, if I manually downshift into second the car will rev match as it should but moments later I get what feels like a really hard downshift. I mean hard. You can feel it in the car.
Is this just normal for a higher stall convertor?
Or is something else going on here?

Now this only happens if I 'manually' downshift.
If I dont manually downshift it feels like a normal trans with a 'shift kit' in it.
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Old 09-26-2025, 08:02 PM   #2
1JEWLDSSRS


 
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Quote:
Originally Posted by b4wheeler View Post
I want to ask this here to see if this can be fixed in a tune.

Just had convertor and gears installed in my car.
Had a tune emailed to me.
Car runs great.

One little issue.
When in manual mode, if I manually downshift into second the car will rev match as it should but moments later I get what feels like a really hard downshift. I mean hard. You can feel it in the car.
Is this just normal for a higher stall convertor?
Or is something else going on here?

Now this only happens if I 'manually' downshift.
If I dont manually downshift it feels like a normal trans with a 'shift kit' in it.
Mine does the same thing, but only when I downshift from 4th to 3rd, that hard "jolt" you feel I think is the converter locking, I believe. Mine has always done that. My tuner has mine setup to lock in manual mode, maybe your tuner did the same. He has it tune for what he called "manual auto lock", so anytime I touch either the up or down button and put it in manual mode, it is set to lock up... It could be just how it is tune, you'd have to ask your tuner how he has it all set. My suggestion is do like I do, I don't use manual mode to downshift at all, unless I'm sitting still and want to start off in first or second and upshift myself. Let the converter and computer do its thing down shifting automatically.
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Old 09-29-2025, 08:36 AM   #3
b4wheeler
 
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Drives: 2011 Camaro 2SS Vert
Join Date: Oct 2015
Location: Cordova, Md
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I contacted the tuner and he said it wasnt a tune issue and that the trans tcm had to relearn the driving habitys.
I have to trust him because he is one of the most reputable builders and tuners in the country.
I kinda thought it was what you said. Just the convertor locking.
I am just going to do what you do, and not down shift unless it is to get into a better gear for roll racing or just messing around on the street.
Otherwise let the trans do what it is supposed to do.

Thanks.
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Old 09-29-2025, 12:24 PM   #4
1JEWLDSSRS


 
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Quote:
Originally Posted by b4wheeler View Post
I contacted the tuner and he said it wasnt a tune issue and that the trans tcm had to relearn the driving habitys.
I have to trust him because he is one of the most reputable builders and tuners in the country.
I kinda thought it was what you said. Just the convertor locking.
I am just going to do what you do, and not down shift unless it is to get into a better gear for roll racing or just messing around on the street.
Otherwise let the trans do what it is supposed to do.

Thanks.
Yes sir. And like he said, the TCM has to relearn your driving habits in the "auto mode". And like I said, I leave it on "sport mode" all the time and let the computer do its thing, unless like you said, ya want more out of that certain gear. Enjoy!
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TSP STAGE 3 CAM,231/246 @112 LSA 614/641 LIFT, CIRCLE D 5C-4200-4500 CONVERTER,LOD INTAKE.CORSA EXHAUST. DSS 1 PC DS. PEGASUS SOLID CRADLE MOUNTS. 486RWHP/475RWTQ.LOTS MORE.
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