Erratic shifting, won't up shift on hills above 50 KP/h.

Vehicle never worked properly since purchase, skipping and/or refusing 4'th gear. Issue raised with dealer and told this was normal part of fuel optimization programming.

Following this, heavy rain caused vehicle to avoid shifting into 6th gear(5th only). Mechanic looked it over, but found no potential issues.

Most recently, vehicle refusing to shift into 6th gear wet or dry as well as shift up above 50 KP/h. Also noticed that it stays into gear when going downhill, running against engine. Similar to manual mode.

Observations; manual mode works, though will not override refusal to upshift. Vehicle hitting hard between shifts. Appears fine under 50 KP/h

Any ideas or suggestions?


PS. Mechanic tried to get codes from van but reader did not appear compatible.

 

There were several TSBs published for shift problems around the 2012 time frame. They involved reprogramming the PCM. Were any of these done?

The only thing a DIYer can do anymore without opening up the transmission is inspect the electrical connections and change the fluid and filter. A shop will have to determine what's up.