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Posted

What are people s experience with them and did anyone have a bump from behind feeling and have them improve on this terrible characteristic of drivability ( sometimes it's worse than others and my dealership just saying " yes, it's normal.just how these trucks drive" but I don't buy it...they don't want to waste there techs time to try and diagnose it so I'm looking for help possibly from blackbear tuning if I feel that it could solve this by tuning?

Posted
What are people s experience with them and did anyone have a bump from behind feeling and have them improve on this terrible characteristic of drivability ( sometimes it's worse than others and my dealership just saying " yes, it's normal.just how these trucks drive" but I don't buy it...they don't want to waste there techs time to try and diagnose it so I'm looking for help possibly from blackbear tuning if I feel that it could solve this by tuning?
I had that bump from behind feeling when it would shift from 3 to 1 coming to a stop. I fixed it by doing a relearn. Let me dig it up...

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Posted

Here it is:



Ok it seems to be fixed. Followed the C1 relearn outlined here:
 
http://gm.oemdtc.com/492/transmission-adaptive-functions-and-correcting-low-mileage-harsh-shifts-2015-cadillac-chevrolet-gmc
To Learn C1 (For 6-7 or 3-1 Shift)
 
Pressure & Volume Learns:
Note: It is recommended to utilize a road with a speed limit between of 30-45 mph (48-72 km/h) for this procedure.
 
Shift the transmission into 6th gear with the PRNDM in the M position. Obtain an engine speed between 1000 and 1600 rpm. Maintain this condition for a total of about 5 miles (8 km). Cruise control may be used and has been found to result in faster learning of the clutch values
 
 
Towards the end of the 5 miles I could feel the trans hunting around between 5-6 when cruising around 44mph.
 
 
It's smooth as silk when coming to a stop now. Friggn computers.
 
-tapa


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  • Thanks 1
Posted
Wow, if this works...
I'll be so happy!
Thanks, I'll try anything at this point
It worked for me! Went out early one Saturday morning and fixed it in an hour.

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Posted

I've been dealing with it for 3 months now( bought it used and all dealership knows is "yes it's completely normal")

If terrible is normal then yes it" normal"

And if slot of people complain about it and it never gets fixed then yes it becomes"normal"

Man I can't wait to see if this fixes it!

Serious props to you for helping me out...

Thanks, if for nothing else giving me hope just maybe it's a simple fix b/c it sounds like exact same issue!

Posted
I've been dealing with it for 3 months now( bought it used and all dealership knows is "yes it's completely normal")
If terrible is normal then yes it" normal"
And if slot of people complain about it and it never gets fixed then yes it becomes"normal"
Man I can't wait to see if this fixes it!
Serious props to you for helping me out...
Thanks, if for nothing else giving me hope just maybe it's a simple fix b/c it sounds like exact same issue!
Well keep me posted. I want to know if it works too. Best of luck!

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Posted

Do you remember if when you did this relearn procedure if your tranny would have been up to 131deg f, as seen in attached screenshot?

Supposably it won't start into a learn type mode until it's up to this engineer set temperature...

Screenshot_20201125-121004.png

Posted
Do you remember if when you did this relearn procedure if your tranny would have been up to 131deg f, as seen in attached screenshot?
Supposably it won't start into a learn type mode until it's up to this engineer set temperature...
Screenshot_20201125-121004.thumb.png.42968eba86daa070b570cb6a815d3bbb.png
Yes it was higher than that

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Posted

Ok cool, thanks for the reply.

So when you did this relearn procedure

You just drive in manual 5th gear and maintain the rpms shown for 5 miles and then switch back to "D" and that's it?

 

Posted
Does this also work with 6.2 Denali ??
Yes.

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