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View Full Version : making auto stay in 1st gear



minytrker
May 31st, 2006, 01:56 PM
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
May 31st, 2006, 02:31 PM
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
May 31st, 2006, 08:46 PM
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
June 1st, 2006, 09:40 AM
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
June 1st, 2006, 10:05 AM
try the upshift tables

Throttle position Vs Road Speed

joecar
June 1st, 2006, 10:20 AM
As Ty said, try setting D0913 to 255 and see what it does.

minytrker
June 1st, 2006, 12:03 PM
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
July 9th, 2006, 04:39 PM
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
July 10th, 2006, 12:05 AM
Never messed with it anymore.