I am looking at buying a used 2009 Honda CR-V with 150,000 I'm.  It has been well maintained but has had various owners.  Shifts and drives great!  Only concern is an occasional issue.  When you slow down for a speed bump then accelerate after sometimes there is a thud and you can feel it in the transmission or gear box, I think.  On occasion after coming to a stop at a light or stop sign when you take off you can experience that thud.  Shifts through all the gears fine after that and in say an hour of driving around town without any speed bumps only felt it twice.  It's not really loud or forceful, but it's there.  Sometimes lighter or stronger.

I've been told to change the transmission fluid.  Some even say to change it three times with a short drive in-between.  Others have said it may be the clutch solenoid letting the car get out of first instead of it staying in first until you but it into R, P or N.  Some have said to clean the filters in the solenoid, others say to replace but only with Honda original part.  Some say change the differential oil as well.  Any thoughts?  If it's a relatively easy fix no problem.  If it's a sign of a big potential problem then it is a major concern.  I do not know if the car has had a major service.  Do not know when any of the fluids have been changed.  I am American but retired to Brazil and live in a small town.  Not a lot of faith in local mechanics here.  Not a ton of CR-Vs here.  Not like the states.  There is a Honda service center about 45 minutes a way where I can get it serviced.  But I want an idea of what I might be looking at here.  Any advise is greatly appreciated.