I hope this clarifies downshift and SSP. You don't manually downshift as part of SSP. Moving the shifter forward while in SSP takes the truck from 5th or 6th or even 3rd gear (I think) to 4th. This takes the truck out of SPP and back to the manual shifting normal transmission set up. It stays in 4th gear until I move the shifter to the right (normal transmission automatic shifting setup) and then to the left (SSP position) again. A bell confirms you are in or out of SSP. I manually downshift (leave SSP) when coming to a traffic light if I want transmission assist. It is very smooth. And I downshift almost all the time merging into highway conditions, with the truck shifting into 4th gear automatically (again, very smooth). To get back into SPP I move the shifter to the right (into the normal shifting pattern) and then back left into SSP. And as I said above, the bell sounds when SPP is engage again and when leaving SSP.