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: Allison shift timing and TCC


04forme
03-17-2010, 11:53 AM
I was wanting to alter the mph that the lock up comes on in 5th gear from 50mph to 45mph in pattern "A" and also lower the shift point mph from 60mph to 50mph on the 4th to 5th gear in pattern "D".
I lowered the values from the stock program pulled from the tcm and re-saved them to a new file name. Then did a complete reflash to the tcm. Test drove the truck and it didnt change anything.
Pulled the file back off the tcm to verify and the tables are the way I set them. And they are. But why didnt this show up on the test drive?? Thanks for help!
BTW this is a 2004 LB7 with DSP5 installed as well. Im sure I must be missing something??:confused:
Thanks

thefermanator
03-17-2010, 07:00 PM
For starters pattern D is 4X4 low not tow/haul, tow/haul is pattern B. And I would not lower the 4-5 shift in tow haul at all as there are tables that you can't see and adjust that will interfere(tried this and you won't like it). Also remember that the ALLISON TCM shift points are set for 4.10 gears with a 245/75/16 tire height. Regardless of what your ECM is set for, the TCM is still set with it's own points. So if you look you will se that the stock setting is 44.7 MPH for lock-up in 5th from 0-43.8% throttle. If you want it to lock-up 5 MPH lower, try putting in 40 for those tables and then blend it in and try it.

04forme
03-17-2010, 09:12 PM
OK so the tables listed here that I copy and pasted from my efilive window are wrong.
Thanks for the tip!
Was this just a typo error in the programming gurus??

Pattern A = 'Normal' mode shifts, when the selector is in 'D'.
Pattern B = '4WD Lo' mode shifts, when the selector is in 'D'.
Pattern C = 'Hot Transmission' mode shifts, when the selector is in 'D'.
Pattern D = 'Tow/Haul' mode shifts, when the selector is in 'D'.

I will leave shift points alone in TH mode and try to just lower the value you recommended for the lock up in 5th. Thanks for the help

04forme
03-17-2010, 09:53 PM
Ok, I tried thefemenators suggestion and it wouldnt work on mine, nothing changed same lock up apply as stock, it shows in the tables that the reflash did save to the tcm. I must be doing something wrong...
What would keep this from not working??

EFI Support
03-17-2010, 10:24 PM
There has been ALOT of time and effort spent on the labelling of these 4 patterns.

When we initially released the software, some had issues, others didn't. After ALOT of research with a couple of members who were having problems we made changes to our software. Shortly after, some other members then advised they never had problems initially but now they do.....the result was that we returned the software to it's inital release status.

The upshot is the software is what it is. You may need to change each of the 4 patterns independantly to determine what works on your vehicle. It may very well be that the patterns are configured differently in different OS's.

Cheers
Cindy

04forme
03-17-2010, 11:12 PM
Cindy, Thanks for your fast reply! That clears up some possibilities. I will try some more experimenting.
Thank you!