So I've got some AT-205 I want to use in my 93 altima engine. It's got a crankshaft seal leak, and I'm sure all the other seals are getting brittle too. I'm thinking this will possibly fix the crankshaft seal and recondition the other seals. I'm planning a 3 hour drive to Vermont later this month, and if AT-205 is best applied on a long trip that would be the opportune time. Or is it better to let it work on a series of normal everyday short trips? Do I need to change the oil afterwards? Should I apply the AT-205 before the long trip? Thanks.