6L80E T43 Replacement

[roysatikas]

Thanks to all for the info posted on our forum!
Yes you can do a Write Entire to a new T43.
Background: I rebuilt a 2007 6L80E from a Yukon (6.2 LS3 and 6L80 now in my 91 Camaro) from the case, most parts replaced with upgraded Sonnax equipment. Tuning of the trans has been an adventure but pretty good now.
One of the few parts not replaced was the T43 but I did rebuild the fluid pressure switches. Recently had some trans problems with a P2714 (Pressure Control Sol D perf/stuck OFF) and trans going into limp mode. P700 comes with all trans issues (Transmission Control System Malfunction) also as a bonus P1682 which is Ignition Switch Voltage Low: Ignition 1 Switch Circuit 2-there is a >3volt difference between the ignition main relay signal and the power train relay signal circuits for <1second.
My T43 GM part number printed on the case assembly of the T43 was 24240651. I purchased a Dorman SP 609-004 which covers twelve different GM part numbers. Go on the Dorman website to cross reference which Dorman will work for you as they have many part numbers to cross reference/work with your GM T43.
Auto Zone had this covered at $564 + $305 core charge. Not cheap but now I have all new components and everything works great.
Prior to trans and T43 removal (had some work done on the converter) I read the T43, after instal of the Dorman I did a Write Entire and everything works!
Sorry for the long write but my Write Entire was successful.

I wanted to share my success with this as there were yes you can and no you can?t accomplish this posts on our form
Thanks to everyone,
Roy

[TheMechanic]

So did you do a read on the new one to verify if it was a rebuilt that had an OS already installed? Or was it a truly brand new dealer style with no programming of any kind.

[gtstorey]

Dorman with a high core charge, my money is on a rebuild with OS installed.

[blindsquirrel]

Anybody here old enough to remember when new hard drives had to be low level formatted before you could do anything with 'em?

A new-new T43 doesn't even have the code in it to initiate communications that allow it to be detected by aftermarket software like HP Tuners. If it can't be detected it can't be written. GM tools are able to write the low level stuff before programming. Once that low level stuff is present it can be detected and written with aftermarket tools. The low level stuff doesn't get erased when a module is rebuilt even if it gets the old calibration wiped.

[2xLS1]

I've seen over 100 new right out of the AC Delco box T43s and they all had 4 segment calibrations in them that could be over written.

[roysatikas]

Thanks for the replies. No I did not read the new Dorman unit as they are rebuilt.
Not cheap but all new components and no issues.
and core returned to my local Auto Zone