01 merc mountianer trans question

ive got an 01 mountianeer that is having trany problems. its awd. when it goes to shift into third it will rev way up and slam into gear. but if you let off the gas just before its ready to shift into third it will go in. it made the engine light come on. i put my mac code reader on it and it says its the shift silinoid. can anyone tell me where the shift silinoid is located and how much of a job it is to change it. my local trany guy said he could rebuild it for $1800 but it may not fix the problem. any info would be very helpful
thanks tim smith

my wifes old PROBE did the samething...had the same problem...and if i'm not mistaken..the part your looking for in under the valve body....it cost her 1500.00 at the time to have fixed....


My '98 mountaineer has the same problem...but no light...and only does it when i have my foot to the floor to get onto the freeway on the on ramp.....or running a Jeep LARADO...have to show the mopars who is the finer of SUV's...lol...lol...BUT STAY AWAY FROM THE srt-8's....:)

mine pegs the tach at 4.5-5k stays there for the longest time then hits hard...