[hatzie]

I modified the 4L80E transmission shift settings this morning.
The driving manners seem to be improved.
Specifically it's not sliding and slipping into 3rd and 4th gear when I'm below 1/2 throttle. Not banging into gear at partial and full throttle either.
The transmission temperature isn't climbing at all now over a driving distance that normally would see the gauge at the first large division and the instant fuel mileage on the dash now shows about a 2-3 mpg improvement... usually I see 12-13mpg and I was looking at 15-16mpg on this trip. I'll post later if it's really that much of an improvement or just the way I drove over to Warren this morning.

Again... I view changes like this with a healthy dose of skepticism. We'll see, when I re-fuel it, what it really did to the fuel mileage. On the surface it appears that I'm not turning as much horsepower into heat in the transmission but the numbers will speak for themselves.

Fairly sedate and conservative changes. Nothing super drastic.

1. Modified the force motor table in a fairly conservative manner.
2. Copied the Performance (Towing) Upshift pressure tables to the Normal tables.
3. Copied the Performance (Towing) Shift Time tables to the Normal tables.

If you're interested in what I did download HP Tuners VCM suite then load and compare these setups.

DJH_2005_Silverado_2500HD_6.0_Stock_265-70R17_Tires_Only.hpt

DJH_2005_Silverado_2500HD_6.0_Copy_Line%20Pres_and_Shift_Time_Performance_to_Normal_and_10Percent Force Table.hpt