99 sierra hard shifts

gwukena wrote:

99 silverado 4wd ext cab 5.3
Predator U7198 Software rev 2.12

After installing either predator tune, giving 3/4 to full throttle at 1-2 shift, code p0748 is set. Trans shifts hard, if I clear code trans operation normal until throttle mashed again for 1-2 shift. Shutting off truck and driving normal okay, code set once throttle mashed again for 1-2 shift. Does not set this code with factory tune.

Please help
Gary

Same problem as him.

99 sierra 2wd reg cab 4.8
predator u7198
Software rev 2.11

Can I also get this is the tune?
In alaska there is nothing above 91 octane.
I have a k&n FIPK ,granatelli maf, and 3 inch dual exhuast.
Thanks ahead of time.

Attached is my factory tune

Man love the new tune! Thanks Johan.

Cool cool, i sent you the EGR delete tune this morning.