auto transmission shifts hard on 2009 Hyundai Sonata

auto transmission shifts hard when driving some of the time, mostly downhill

Asked by for the 2009 Hyundai Sonata
1 answer
You should still be under warranty, I suggest having the Hyundai dealer look at this to see if there are any diagnostic trouble codes stored, Technical Service Bulletins related to this issue or software updates for the transmission control module.
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