TC Won't Stay Locked With EFILive Tune

duramaxdiesel

Dmax Nut
Oct 23, 2008
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I'm just curious if any of you guys have had a issue like this or know someone who has? On the stock tune my truck shifts and drives perfectly. When I install a tune it pulls very well and I'm happy with that. What I don't like is that when I drive and the TC is locked the second I lift my foot off the throttle the TC unlocks. It will lock up again if I get into it. I could be going 70, 80 or whatever speed and it still unlocks when I lift my foot. Really annoying when I'm towing. I tried Tow/Haul and it works intermittently at best. Even using Manual Mode I get the same results.

The truck is a 2008 LMM. All stock other than a CTS for gauges and a DPF delete tune with some more HP for towing and all around fun.

If any of you guys could shed some light on this I'd really appreciate it:thumb:

Thanks,


Nick
 

JoshH

Daggum farm truck
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You need to check all the TCC apply and release tables and also the TCC max and min duty cycle tables.
 

duramaxdiesel

Dmax Nut
Oct 23, 2008
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Thanks Josh. I'll have my tuner check that out and see what he says:thumb:

Tomorrow I have another big load to tow and having this happen all the time is a PITA.


Nick
 

paint94979

Beer Nazi
Sep 18, 2006
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Who tuned your truck? My apply and release tables are quite modified... That's what it took to get my converter to lock before 4th gear
 

SSchmi5519

LLY Cult Leader
Oct 19, 2008
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Who tuned your truck? My apply and release tables are quite modified... That's what it took to get my converter to lock before 4th gear

I did. He's reading lockup on an Edge CTS, and I wasn't quite sure if that was the problem. It happens on his DSP5 and on a single tune, both of which were created with his original stock tune. I have a few more ideas on how to go around this, just need a little time :thumb:

Its just very strange to me that this is happening. Cant say ive even ever heard of it :shrug:
 

C.bowles2

2005 lly duramax
Nov 16, 2013
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I wish I could help but I have a quick related question (sorry not trying to hijack the thread) when should the TC lock up, on my lly it only locks in 5th gear & at higher speeds and I can feel it lock in and lower the rpms. I'm reading it with a cts.


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Dozerboy

Well-known member
Jun 23, 2009
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I wish I could help but I have a quick related question (sorry not trying to hijack the thread) when should the TC lock up, on my lly it only locks in 5th gear & at higher speeds and I can feel it lock in and lower the rpms. I'm reading it with a cts.

Sent from my iPhone using Tapatalk

If your not in TH that sounds right
 

JoshH

Daggum farm truck
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2008 trucks used the A40, so unless someone changed it (which wouldn't make much sense), that's what it has.
 

Harbin_22

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Dec 4, 2010
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2008 trucks used the A40, so unless someone changed it (which wouldn't make much sense), that's what it has.

Haha, I know of at least one truck that is lol. I swapped mine with a local farmer and he no longer owns the truck. If somebody ever tries to mess with it, they will be all screwed up
 

meshanic

All In Trucks
Dec 9, 2010
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Haha, I know of at least one truck that is lol. I swapped mine with a local farmer and he no longer owns the truck. If somebody ever tries to mess with it, they will be all screwed up

Ha Ha I had an 09 LMM with big twins I was tuning so I swapped the tcm with a farmer's 08 tcm. Now there's 2:D
 

JoshH

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Ok, as long as the truck wasn't owned by some farmer... :roflmao:
 

jkholder09

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Jan 8, 2012
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2008 trucks used the A40, so unless someone changed it (which wouldn't make much sense), that's what it has.

Well I was kinda thinking it was a measured torque issue (I am not sure what the technical term is, but I am referring to the al50 and how it determines engine torque based on trans slippage) maybe but the al40's really don't do that feature in the strategy from what I understand.

Do you think that could effect drivabilty?
 
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JoshH

Daggum farm truck
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Well I was kinda thinking it was a measured torque issue (I am not sure what the technical term is, but I am referring to the al50 and how it determines engine torque based on trans slippage) maybe but the al40's really don't do that feature in the strategy from what I understand.

Do you think that could effect drivabilty?
I've never heard of the TCM doing that, but I've never played with the A50 TCM any.
 

jkholder09

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Jan 8, 2012
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Ben tyler was talking about it somwhere.
I just can't remember where.
I have no idea if it would create a problem like this.
It was jjust stuck in the back of my head and I thought I would ask.
Thanks josh:thumb: