Yes. You can upload your audiobook the same way you do with music or eBooks. You need a barcode and an ISRC for every chapter. Make sure that your metadata are correct, otherwise your audiobook cannot be distributed to Audible
. Audiobook genres are particularly important if you want your audiobook to be listed correctly in the stores.
Audio files longer than 10 minutes will be distributed to iTunes as "Bundle Only", as they can be only purchased as a complete album.