Its always a good idea to park without any pressure on the transmission, i.e., wheels against curb or apply parking brake in neutral before you go to park. I do this ALWAYS when not perfectly flat. I actually put it in neutral before every park to make sure its not rolling even a little. I've got my wife to figure it out too! (she doesn't understand why I think its important, but she does it so she doesn't have to hear me)

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2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900