I bought a sonata 09 with 250k miles on it. it has some leakage on the transmission and has hard time shifting down when the trans oil is cold in cold weather. I have to put it on manual and keep the gear on 1 or 2 for some minutes to prevent the hard downshift when I break. but the upshift is fine and it always works fine.
the first question is, does changing the tranny oil (or even flushing the oil) would enhance the shift performance? it costs about 160$ on Valvoline to change the transmission fluid as I got a quote on phone. the guy in this link says that I should not change oil on a transmission that is not working fine
the next question is, does it worth to even try to fix the transmission leak? it seems that it is going to cost too much, so much that maybe I have to spend half of the price I paid to buy the car for this single repair. I went to a `good rated transmission center` near me and they said they are going to charge 215$ just for the “inspection” and I can’t afford it right now.
PS:
I have no idea if it has ever been changed before.