Do P0751 code not shifting to 4th gear cause for new transmission?

Question

2002 Ford Focus was diagnosed with code P751 not shifting to 4th gear. Transmission need to b replaced  with soft part overhaul of $1795.00 cost. Mind you transmission was already replaced in 2014.  Also mechanic speaks about clutch. Does this diagnosis sound correct and why?

Answer 1

P0751 Shift solenoid A

Yes this does sound correct, the shift solenoid will have to be replaced, this is caused by the shift solenoid failure, plus the the transmission fluid and the filter