Weird Transmission Shifts?

[CapeCod4runner]

Hi All,
My girl friend lives up in Maine and I live on Cape Cod where it is very flat. When I bring my 4th gen up to Maine where it is very hilly the transmission seems to downshift a ton, even when I am on flat surfaces? Ill be cruising at 50 in 3rd gear for a good 30 seconds before the transmission realizes it is flat and it suddenly upshifts. Does anyone know why this happens? I'm guessing it has to do with the fact of all the hills

 

[4WD 4RNR]

These trucks learn your driving patterns, if you are hard on it then it will shift different and vise versa.

 

[kevinpt]

These trucks learn your driving patterns, if you are hard on it then it will shift different and vise versa.

this might explain why my truck likes to go into first after i take a corner at like 20mph

 

[BlackWorksInc]

If I remember correctly, if you disconnect the battery for I think its either 10 or 30 minutes it should reset the learned data and the vehicle will have to relearn your driving pattern and relearn idle and such.

 

[CapeCod4runner]

I think thats part of the VVT-i system? like trying to conserve gas and what not?