I recently purchased my 1st diesel truck. It is a 2005 Dodge 5.9 3500 (single wheel) 4x4 automatic quad cab. I put a K&N air filter in it other than that it is stock. It has 86000 miles on it. I've noticed when it idles I get a hot oil smell in the cab of the truck. Is this normal. I've looked all under the truck and can not find any oil leaks. Sorry for the basic question, but I've read most of the post on here and could not find it. Thanks.