Few new (to me) truck questions TC /accell pedal & allison

[ssybert]

Hey guys... I've had my 02 for about 6 weeks now. The other day I noticed something... I'm not sure if this is normal, but dont recall seeing it previously. When I accelerate I can let off the pedal at any time and the RPM's will drop to roughly 1k. If I'm going over 50 and the TC is locked if I let off for 1 second or 30, if it's still over 50MPH the TC STAYS locked. it wont unlock and the RPM's wont drop down to idle until the truck gets under 50 mph. Is this right?

Next question... My accelerator pedal seems to be too low to the floor. Most vehicles the pedal is stopped from going down any further by an intentional stopper of some kind. This truck the rug stops it and if I push REAL hard to push the rug out of the way, it will pickup alot better. Anyone else seeing this? Do I need to get under there and do some funny work?

Lastly, when I stop with the drivers window down I can hear some sort of intermittant ZZZZZZZZ sound. It sounds like something engaging then dis-engaging. I dont know if this is normal either.

I DID change the fluids with Dexron III fluid as well as a spin-on filter change.


Any insight would be appreciated.

Thanks, Scott.

[DmaxMaverick]

The tranny behavior is normal. The TC won't unlock like on other vehicles/trannies. In T/H mode, that MPH # will be around 20. Brake input won't cause a TC unlock, only MPH, or RPM, if you have changed tire size. 93% pedal input will cause the TC to unlock if the speed is near the "threshold".

The carpet is the pedal stop in most cases. It doesn't have a "stop block", like on some previous M/Y's, before Duramax. Some owners have mod'd the APP so the carpet doesn't interfere with APP travel. Some interfere, some don't. Only way to tell is seat-o'-the-pants, or a scanner. On mine, I have to depress slightly into the carpet to get 100% APP, but not excessive. Some have reported they have to stand on it to get 100%. It can be adjusted to some degree. Hook up a Tech II or Predator to read the APP to confirm what yours is doing.

Can't say for sure what the noise is. The A/C compressor will cycle under some circumstances, even when you haven't selected A/C. Anytime you have selected DEF or Recirc, the compressor will cycle, whether you have the A/C on or not. When you hear the noise, make a note of the HVAC control positions. When it is selected to fresh air and upper vent (any position left of 12 O'clock) with A/C off, it should not cycle at all. If you have auto A/C, it can cycle at any time without any input from you.

If that's not what you are hearing, describe it further with more detail.

Cheers