So I have a 2008 tacoma with a 5 speed automatic transmission that doesn't like to shift into 5th when it's cold. It only really does this when it's below - 10 celsius. Once the truck warms up it shifts fine but at first it can take several minutes on the highway before it finally shifts into 5th. I have a feeling it's a computer problem but I don't understand why it would only happen when it's cold out. The colder it is the longer it takes to shift to 5th and when it's above 0 celsius, it shifts perfectly fine. Anyone know what's going on?