Diablosport Forums

I have a DiabloSport T1000 and I see in custom tune I can change the downshift mph, upshift rpm, upshift mph, upshift rpm & tps ... I change some spec in downshift mph and in upshift mph and I don't see the difference. The probleme is when I drive on the highway, my truck go in overdrive between 55mph and 60 mph and when I want pass a car, the transmission won't shift back fast from one gear, I need to push the throttle pedal at 50% for downshift or kickdown.

Sorry for my english !

Sierra 1999 sl 4.8 RWD
Aire Intake
Exhaust Flowmaster Super Truck
P275/70/16

change the downshift mph... go down -5 mph... will make it downshift sooner...

I try it today and not working. When i go to see to modify In Downshift mph is writing
downshift 2 to 1
2 to 1 tow/haul
3 to 2
3 to 2 tow/haul
4 to 3
4 to 3 tow/haul
and in the downshift 4 to 3 and 4 to 3 tow/haul is writhing 235.7 mph

the PCM
9373372 Operating System
16263835 Engine
9357883 Engine Diagnostic
16264165 Transmission
16264332 Transmission
Diagnostic
16253336 Fuel System
9373392 System
16253353 Speedometer