Cruise Control Unsteady Speed

[ls1mike]

Not sure which forum this should go in because not sure if it is ECM or TCM but I have an '11 5.3 truck on 35s and when you turn on cruise control it drops ~3 MPH then rises back to the desired speed and will continue to hold properly. This can be annoying because at low enough speeds it will downshift. The speedo is correct and my other speed data should be correct. Is it the factory ABS or other computer that needs a tech2 reprogram? Suggestions would be great thank you.

[Brian1]

To eliminate EFILive if you run all stock tuning does it do it?
Next i assume your tuning has corrected the speedometer. If so then just take your stock tune and correct the speedometer and see if it does it.
If it works fine and then use your fully modified tune then maybe something in it is the cause.

Brian

[ls1mike]

Reducing H0105 TIRE SIZE CORRECTION seems to have the problem solved.