The following error codes are popping up P0810, P0785, P0740, P0735 on a 2001 S60 2.4T that I am looking at to buy. The car shifts and downshifts hard in 1st and 2nd when taking off about 15 min after driving it. Can anyone tell me if this is an easy cheap fix or if it’s complicated and may need a new transmission. The car has 122,000 original miles