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View Full Version : Tow Haul...Zero Throttle...Downshifts



killerbee
February 9th, 2011, 04:28 PM
OK, been wanting to post this for awhile now. There is something else we need access to. Just can't put my finger on it.

When off the pedal, the zero throttle setting does nothing. If I give it just a smidge of throttle, the downshift table kicks in. This is especially obvious with the 5-4 shift. I suspect it has to do with the grade braking downshift algorithm. IOW, it seems that the downshift schedule is governed by other tables we don't have (yet :) )

Ross, can you help?

THEFERMANATOR
February 9th, 2011, 05:22 PM
I believe all of the zero throttle downshifts are contained in other tables as I know teh lock-up zero throttle table doesn't respond properly in regular mode.

killerbee
February 11th, 2011, 02:41 AM
The zero throttle downshift works (clarification). But only if the speed is below the zero throttle entry when you take your foot off the pedal.

I will post an example in my next post, in hopes that we can finally get to work on this. It has been an "accepted" limitation for a long time, and I want to generate some interest/motivation to resolve it. I have done a lot of testing thus far. I am buying a couple of TCM streams on faith. :)