Front seal bad? Any guesses

[4by4runr]

So I'm still looking for my 4Runner and found one here in town - I'm going to check it out tomorrow am. The seller said his shop said the "front seal is going", seller didn't have the record in front of him and couldn't remember what seal.

Anyone here have any guesses what this might be? 2006 v6 150k
At first my thought was the valve covers but those aren't really called front seals.
And no I don't know a whole lot about auto repair.
Thanks all!

 

[CXS]

Crank seal? Cam seal? Might be an expensive repair but I don't know much about the V6.

 

[radlynx]

it's probably the front differential seal.

So I'm still looking for my 4Runner and found one here in town - I'm going to check it out tomorrow am. The seller said his shop said the "front seal is going", seller didn't have the record in front of him and couldn't remember what seal.

Anyone here have any guesses what this might be? 2006 v6 150k
At first my thought was the valve covers but those aren't really called front seals.
And no I don't know a whole lot about auto repair.
Thanks all!