Nissan Repair: Quest-Villager transmission, mercury villager, column shifter

Question
Hello i'm hoping you can help me with this strange problem with my 95 Mercury Villager. The truck runs great except that once in awhile, the tranny or maybe just the linkinge or steering column shifter, i don't know,  does not engage in reverse.
This is an intermittent problem and the transmission does not slip or jerk or hesitate in any way when driving normally.  It just does not engage in reverse, or engage completely sometimes. Sometimes it's just very slow to engage. When it does engage reverse which is probably 60% of the time, it works perfectly. Weather it's 20 above or 20 below does not affect it. Weather the engine is warm or cold it still reacts the same way. I can drive with a full load uphill and accelerating and the tranny does not slip.
The transmission oil is nice and pink and does not smell burnt.
The vehicle has 205,000 kms or about 130,000 miles.
The truck has been well kept and i'm the second owner.
Is this the beginning of the end for the tranny?

Answer
The reverse servo is going out and as you describe it is taking its time getting into gear.  But, the rest of the transmission is fine.  So, do you drop the money to get the reverse servo replaced now or wait until it goes out all the way?  The choice is yours.  With over 100K on the car is it worth it?  Or do you trade it for another.  The cost of dropping the transmission is going to be something like $2000.  The van is an awsome vehicle and I love all the goodies they have.  It is an excellent vehicle for doing almost anything so it would be difficult for me to get rid of it.  But, at this mileage you have to weigh the costs to own vs. getting something else.  I would think you could get another 100K out of the engine and such if the transmission was corrected.  Cottman is a good shop from my previous experiences.  I would never go to AAMCO as I have had a bad experience with them so I hope you have luck which ever way you go.