making auto stay in 1st gear

[minytrker]

I can't get a 04 2500HD to stay in first at part throttle. It will shift into 2nd with the selector still in 1st. Im trying to this manually holding it in 1st.

[Tydriver]

Check table D0913.. Mines set at 255mph.. Listed as "Maximum speed before the PCM will force an upshift to 2nd if the gear lever is being held in 1st."

I have an '02 Silverado 1500 5.3L with a 4l60e.

LMK what you find out..

[minytrker]

I have it set at 100mph and it still will shift into 2nd. Its only at part throttle, at wot it will stay in 1st.

[Tydriver]

hmmm I dunno what to tell you.. Thats odd.. Not sure if something is different because of the small platform variances.. Hopefully someone will chime in here

[Rico]

try the upshift tables

Throttle position Vs Road Speed

[joecar]

As Ty said, try setting D0913 to 255 and see what it does.

[minytrker]

try the upshift tables

Throttle position Vs Road Speed

I have messed with those. Its weird if you go wot it will hold out the speed and rpm I want but at part throttle it will shift into 2nd.

[Rico]

Did you solve the problem?

I suspect that Vss is not calculating exact. Mine overrevved so I dropped the VSS upshift until it hit the right RPM. Maybe the tire calculator doesn't change all parameters? Thins is from memory, which is not good in my mind;)

[minytrker]

Never messed with it anymore.