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OK. So if I am cruising on the freeway at 65mph and press the T/H button, should my tranny downshift? This has never happened even when the truck was new.
And when I am going down a hill lets say at 40mph and I press my T/H button, nothing will happen unless I tap the brake, then the tranny will downshift into the appropriate gear to hold me back. This just stopped working.
So what should I look for when cruising on the freeway to ensure my T/H is working.
Thanks
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Your tranny should work close to this.
I just read the info in the link. It is different from what I experience.
I have a March 3rd build 2003. No reprograming. This is what I have.
No load, no fuel pedal coast down from 70 mph in Tow haul mode.
5th to 4th down shift locked tq at 55 mph.
4th to 3rd down shift locked tq at 45 mph.
3rd to 2nd down shift locked tq at 25 mph.
2nd to 1st down shift unlocked tq at 10 mph.
Load or no load down a grade, speed and lenght of grade dependent.
I can tap the brake pedal from a speed of 70 mph on a downn grade and get a downshift. The truck may or may not hold its speed depending on the steepness of the grade. If I need to slow the truck I apply the brakes and the tq stays locked and the truck slows. If I have slowed down to say 60 mph and take my foot off the brake and the truck starts to speed back up from the grade I can tap the brake again for another down shift. It seems that the down-shifts are RPM dependent as the programing won't over rev the engine.
OK. So if I am cruising on the freeway at 65mph and press the T/H button, should my tranny downshift? This has never happened even when the truck was new.
And when I am going down a hill lets say at 40mph and I press my T/H button, nothing will happen unless I tap the brake, then the tranny will downshift into the appropriate gear to hold me back. This just stopped working.
So what should I look for when cruising on the freeway to ensure my T/H is working.
Thanks
[/ QUOTE ]
Your tranny should work close to this.
I just read the info in the link. It is different from what I experience.
I have a March 3rd build 2003. No reprograming. This is what I have.
No load, no fuel pedal coast down from 70 mph in Tow haul mode.
5th to 4th down shift locked tq at 55 mph.
4th to 3rd down shift locked tq at 45 mph.
3rd to 2nd down shift locked tq at 25 mph.
2nd to 1st down shift unlocked tq at 10 mph.
Load or no load down a grade, speed and lenght of grade dependent.
I can tap the brake pedal from a speed of 70 mph on a downn grade and get a downshift. The truck may or may not hold its speed depending on the steepness of the grade. If I need to slow the truck I apply the brakes and the tq stays locked and the truck slows. If I have slowed down to say 60 mph and take my foot off the brake and the truck starts to speed back up from the grade I can tap the brake again for another down shift. It seems that the down-shifts are RPM dependent as the programing won't over rev the engine.
