55 chev LS3 conversion E40 T42 mph problems

[AutoRehab]

Thanks to all
I have a 55 chevy car ls3 with 4l65e trans, ecm and tcm are from 2005 corvette vin 1G1YY24U855108969.
Have been able to tune engine with no problems,
my problem is the trans shifts way to soon, 4th gear at 20mph. when looking at trans data with my snap on verus, it shows 158 mph when actual speed is 45mph, Dakota digital dash reads properly as well as ECM, just not TCM, when in the efi-live trans cal for the speedo there is a check box for corvette, transaxle etc, when I uncheck it and apply, close the box and flash pcm.
Then I go back in, and the change did not stay, the box is checked again

[Taz]

It makes it difficult to offer reasonable suggestions - given that you did not post your tunes.

[AutoRehab]

I have been trying to do some other math calcs, the Dakota digital reads 1 mile at 14,000 pulses, the tire size on car is
24/45/18
gears are 4.10
4l65 trans
attatching engine and trans tune
DON05LS2TCM-CS4_0001.ctz
DON05C6A4LS2-CS3.ctz

[AutoRehab]

Also when I try to click on speedo calculator, I get this error

[joecar]

You have to have installed V7 and V8 while logged in as Administrator, and you have to run the software while logged in as Administrator.

[AutoRehab]

I have now logged in as admin, the error message is gone.
I have re flashed TCM with cal posted in this reply as well as screen shot of my snap on verus and speedo.
Speedo is accurate to ECM as well as actual speed with GPS Speedo.
One only thing I didn't mention before is speed sensor was bad and I replaced it with one from 2002 Camaro A/T.
Didn't think this is the problem being ECM and speedo read correctly.
As I mentioned before the Dakota Digital Pulse count on a measured mile was 14,000.

DON05LS2TCM-CS4_0002.ctz

[AutoRehab]

Thanks for the help, I have posted some new info if you have more advise.

Thanks, Don.

[CalEditor]

You have to have installed V7 and V8 while logged in as Administrator, and you have to run the software while logged in as Administrator.

Thanks for helping out Joe

[AutoRehab]

Just wanted to add I don't have vehicle working yet, any help appreciated.
I did not perform install, just trying to help repair. car was brought to me believing trans was bad. ( was just speed sensor) customer has been trying to get tuned for some time now.
was told yesterday to check grounds and dual power to T42 tcm as it could be why it is not holding cal. their wiring is hidden very well and hard to get to, any thoughts before I tear into that?

[CalEditor]

Just wanted to add I don't have vehicle working yet, any help appreciated.
I did not perform install, just trying to help repair. car was brought to me believing trans was bad. ( was just speed sensor) customer has been trying to get tuned for some time now.
was told yesterday to check grounds and dual power to T42 tcm as it could be why it is not holding cal. their wiring is hidden very well and hard to get to, any thoughts before I tear into that?

Brian had contacted me about this.
AC and I go back to 1986