Diablosport trinity tuner for GM - $400 (Rochester)
QR Code Link to This Post
Still in the box, GM tuner #9245. Was on my 2005 Silverado to tow my trailer. Helped firm up shifts and a bit of MPG. Also, much better throttle response. Doesn't work on my new truck. Was over $700. I'll take $400/BO. Forward me your number and I'll call you to come see this. No E-mail replies.