How do you tune a 6L80E transmission?

The main areas (HP Tuners' introduction to transmission tuning):

• Shift points: by speed or rpm, for each mode.
• Line pressure: higher gives firmer shifts; lower gives smoother ones.
• Shift time: the target time to complete a shift, in milliseconds. HP Tuners notes shorter shift times can reduce heat.
• Converter clutch lockup schedule.
• Torque management: torque reduction during shifts.

What performance tunes typically do — per Gears Magazine's look at GM 6-speed tunes:

• Add about 20–50 psi to the shift pressure cells.
• Cut desired shift times from the stock 0.3–0.4 s toward 0.2 s or less, which is very firm.
• Lower the torque-reduction factor (for example 1.0 → 0.7).
• The catch: stock internals then see more torque, which raises the risk of slip and heat, and locking the converter at WOT can shock a stock converter.

After any major change, reset the transmission adapts so it relearns: through VCM Scanner (HP Tuners), or the handheld's relearn function on Holley setups. See transmission tuning.

Want to do it yourself? See who tunes it, and how to learn.