New Allison Software

[David Brady]

Folks,

While at Smith Power Products in Salt Lake City, Ut,
I had the HD4000 tranny reflashed with the latest software.
I was running 0C00ABF008N and upgraded to 0F00ABF005S.
The first 4 digits are the major number of the software. From
0C00 to 0F00 reflects a 3 level later revision. The last 4 digits
are the minor number of the software release. ABF means that
identifies the 4000 series transmission. My complaint with revision
0C00 was that it hunted for the proper gear when ascending
a hill. She cycled repeatedly thru downshifts and upshifts 'till I
tired of it and hit the down arrow to lock her into the proper
cog. Not so anymore, with 0F00 she downshifts once and stays
there, and the shift points keep the engine at 1750rpm or
above. Very pleased! Another benefit is that the shift quality
is much improved. The tranny learns how to shift by measuring
torque on the input and output shafts, and it changes the quality
of the shift by varying the pulse width of the hydraulic fluid into
each clutch pack. I can no longer feel the downshifts they are so
smooth, the only indication is that the rpms on the tach change.
Very pleased! We also did an a engine oil (synthetic) and tranny
oil (transynd synthetic) lab analysis - everything checked out
well. 70K miles on the LXi and she's just breaking in.

David Brady
'02 LXi, Smokey
Va