I changed my atf fluid on Sunday. the atf in the tranny was brown too....damn, it was dirty....drove it after and the shifts were better...i used penzoil..

dont go to jiffy...do it urself very simple...take off ur right tire, u will see the bolt...just unbolt and drain...

then fill 3 qts of atf fluid and u are done... do it again on ur next oil change and u will be set