McConaughey, 36, bought the vehicle at a 1998 auction and is now auctioning it himself to raise money for Oprah Winfrey's Angel Network, which is assisting in Gulf Coast hurricane recovery efforts, TMZ.com reported.
"I am fortunate enough to have everything I need, and the sale of it will help so many" McConaughey says in the auction posting.
As of Wednesday evening the top bid was $42,400. The auction ends July 27.
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