Hello out there, this is my first post. My 99 1500 4wd 5.9l has been leaking fluid and needs a new gasket. It may not have the origional transmission. The order code under the hood is DGB (4 spd sd) the transmission serial number is pk521 19823aa 3348 6434. Is this a 46re/a518?

 

A 99 has an RE.