I have a Jeep jk with 4.10:1 gears and 35" tires running a 6.0 ls with 6L80E trans. On interstate running 78 mph and 2100 rpm's, with a head wind going up an overpass it will drop down a gear, out of 6th into 5th. Is there anyway of adjusting the drop down point? I would think it should hold that gear longer but maybe not.
I have been messing with downshift max speed to try and control when it downshifts but not having any luck. it was set at 84, i
I have reduced it to 73 and it still kicks down.
Looking for some guidance.
Here is the tune. It is from a 2011 Denali 6.2 so may look a bit different than a 6.0
You are adjusting the wrong parameter for your issue.
Go to Transmission>Auto Shift Speeds>Part Throttle Shift … then all of the tabs for 6th gear.
In the Normal pattern, a downshift from 6th gear to 5th gear around 80 MPH would roughly correspond to about a 65% to 70% throttle opening.
To hold 6th gear longer, increase the downshift speeds in the appropriate cells. Remember that the corresponding upshift speed must always be greater than the downshift speed – or you will have a schizophrenic 6L80 on your hands.