The $2000 oil change

I have a 2006 Ford Explorer V8 that I bought used about a year ago.  As
has happened so many times before with more than one car and shop, I
took the car in for an oil change and the shop performs their "free"
inspection.  Then they come to me with all the recommended maintenance
items, which magically always seem to cost somewhere north of $1500.  So,
for my '06 Explorer with 121K miles on it that runs fine, they are
recommending: transmission drain and refill, remove and replace
transmission oil pan gasket and filter, drain and refill transfer case, brake
system flush [dark & dirty fluid], fuel system service, fuel filter replacement,
spark plug replacement & replace spark plug coil boots...all of which comes
in at $1753 for parts/labor/tax.  I have no idea if any of this stuff really
needs to be done or is advisable.  Several are apparently Ford-
recommended at 120,000.  I'm fearful of the transmission work especially
because I had it done on a 2004 Ford Escape a while back and a month
later, the transmission blew up.  I generally tend to think that if the
manufacturer and certified mechanics recommend something, I should do it,
then I look on the internet and find hundreds of people say don't.  I would
appreciate any feedback.