Hello Everybody!
Ok, I have a 2007 Avalanche with a 5.3L based 383ci, 239/247 cam, 12:1CR, 3200RPM Stall, ported H/I/TB, and LT headers. I have spent the better part of 45 days tweaking the trans tune to get it where I think I want it, and I believe I'm 99% there. For the record, I think the tranny is either stock, or a stock rebuild, minus the converter that I put in. It desperately needs the 1-2 Servo upgrade as well as a Trans-Go shift kit, but I'm just going to drive this until it goes out, then look at either a Monster or maybe consider swapping to an A6.
I'm looking for any advice on tuning the TCC. I am happy with where the apply/release speeds are set, my problem is figuring out the MIN/MAX TCC Duty Cycle. I understand the MAX TCC DC, it's the MIN that I need a little help with. If I utilize the STOCK MIN settings, the TCC will "hunt" while you are in steady state cruise on the highway, about 100-150 RPM up/down. When I raise the MIN values to, say 65% (where they are currently) the hunting is gone. And I just set 65% across the entire range fro the MIN table. Is there any harm to doing this?
Another annoyance is the TCC unlocking in 4th as soon as it detects a "coast" condition, for lack of a better way to explain it. Example: cruising on the highway, CRUISE CONTROL set at 60MPH and 1600RPM, and you go down a slight valley (picking up a couple of MPH) and then start back up the other side. As soon as the speedo hits say 59, the RPMs are at 2000 for a couple of seconds then the TCC re-locks. Just looking for advice on how to minimize, or eliminate this.
Also, can anybody explain the difference between the following shift patterns for the 4L60E, T42 TCM:
NORMAL - (cruise??)
PATTERN A - (Performance??)
PATTERN B - (Pretty sure this is TOW/HAUL, but would love confirmation or correction)
tune file posted below.
Thanks,
Scott