transmission shifts while on the highway on 2000 Nissan Maxima

I have 65k miles on my car. Whenever i drive on the highway and the engine is still cold, it takes about 4-5 miles or 20 min of driving for the car to shift into overdrive. When the car was new the car shift into overdrive right away, but it the last 2 yrs, it takes longer to shift into OD. I read online that it could be some type of solenoid. Is this a transmission problem or just replace the solenoid? thanks

by in Rochester, NY on December 08, 2010
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1 answer 1 comment
ANSWER by , December 08, 2010
dont think it is the soloniod. it may be a sticking valve in the valve body. when was the last time you had the fluid serviced? thats a good start with a valve body modifier added as well. Roy
COMMENT by , December 09, 2010
the fliud was last changed in 2006.