I charge at 7 amps with a .024 cut-off. I program the long lockout to 3500mah as these packs take about 4500mah+ to charge.
Here is something to try guys. Charge and cycle a pack on the GFX with the same settings as above but use a 2 peak setting. Set the re-peak at 6.0 amps with a .01 cut-off. On the next day take the same pack and charge it on the Pitbull and then hook it up to the GFX for cycling. Setting the GFX at 6.0 amps with a .01 cut-off cycle the pack using a single peak. Basically you are re-peaking the pack so make sure to change to single charge/peak.
You will be amazed at the differences! This will trully show how good the Pitbull really is.