Not sure how far it went but I can tell you this, if it is a 4 x 4 they may have played in the surf and that possibly could be deeper than you think. Other wise they could have driven on salted roads. two ways to fix it, do it yourself or take it to a pro and get it done right and with a warranty. from what I saw you are going to needs some parts REPLACED. Sorry my best thoughts, speaking from past experience, if you get new parts make sure they are new and not seconds. I did that from a accident and ended up with rusted parts and no warranty.