Hey guys, I recently bought a 17 Silverado and have been messing with the tq management/line pressure/driver demand to get firmer shifts. I have gotten pretty close to where I want to be, at 1/2-3/4 throttle it will bark the tires on the 1-2 shift, which I like. However, the 1-2 WOT shift is not firm enough to do that. I will post my tune for you guys to look at, I appreciate any help given!
Mike
Be very careful what you change in regards to torque mngt, driver demand and the shift torque factor tables on the 6L80e's. Doing too much will cause extra wear on the clutches and hard parts.
Work with you base shift pressure itself to quicken the shifts and use the on-coming pressure presets to help speed up the shift.
Personally I'd return the shift torque factor back close to stock, increase the shift pressure like 5% at a time where you need it. Then add 5-10% to the on-coming pressure presets to help. Keep shift times around .3000 or so in the trucks.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
Anyone else care to chime in here? Another issue I've noticed is premature lockup on the TCC, in 3rd gear. Can't really tell what I've done that may have caused this, but under moderate acceleration the converter will lock then quickly unlock when at 1/2 throttle or so in 3rd gear. This only happens during the 2-3 shift.
Mine has what feels like a premature upshift at 22MPH which I thought was 2-3 for a really long time. Turns out its the TCC locking up in 4th gear, happens for me usually when I'm going around a corner while letting off gas and then give it gas again. It sucks because I can tune it out but then light acceleration doesn't feel right.Originally Posted by MikeB1985
Also I wouldn't remove TM as much as you are doing. Monitor Torque when you are shifting, I'm trying to keep mine under 80ft-lb. You can dynamically adjust TM by playing with the Shift Torque Factor Adder Modifier Table.
(Shift Torque Factor)+(Shift Torque Factor Adder*Shift Torque Factor Adder Modifier)
so 1-2 shift with:
Shift Torque Factor: 1.0
Shift Torque Factor Adder: 1.0
Shift Torque Factor Adder Modifier Table: -0.50 @ 148 lbft and below:
1+(1*-0.5) = 0.5 or 50%
The stock tune removes something crazy like -80lbft on shift for 1-2 but if you just adjust a static 50% it will remove too much when you are 250+lbft.
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