quick question cant seem to find where i can change this

[shane2500hd6.0]

2003 chevy 2500 has 4l80e i have shift lock enabled but why is it 1 to 2 shifts it wont hold first gear unless im WOT but it will hold any other gear is there something im missing i forgot to change thanks

[horsepowerguru427]

We need a tune and log file to look at, otherwise we're just guessing.

[edcmat-l1]

businessman-looking-into-crystal-ball.jpg

[shane2500hd6.0]

file

[RDF1]

2003 chevy 2500 has 4l80e i have shift lock enabled but why is it 1 to 2 shifts it wont hold first gear unless im WOT but it will hold any other gear is there something im missing i forgot to change thanks

Shift lock as to do with the TCC.

[ECM] 400 - TCC Lock During Shift: When enabled, the VCM will allow the TCC to remain locked during shifts in an automatic transmission fitted vehicle.


Look under D1 Urban. It shows to command 1-2 shift at 24mph at 50% and less.
Over 50% it shows to command 1-2 at 256mph.


You also have your WOT RPM Shifts at 6000rpms but your fuel rev limiter is 5700rpms

[Alvin]

2003 chevy 2500 has 4l80e i have shift lock enabled but why is it 1 to 2 shifts it wont hold first gear unless im WOT but it will hold any other gear is there something im missing i forgot to change thanks

Check D1, D2, etc.. shift tables. Trucks have a safety shift thing where they will shift into second even if the shifter is in 1.