This item was recommended by Amazon ad for BOSS audio, when I took the BOSS & all the other items recommended to operate with the BOSS to a Professional Installing Company whom are located Nationwide, they stated "this harness WILL NOT work properly with your 2004 Silverado diesel HD" especially if you want the volume & channel changer on your steering wheel to work..  The product (harness) needed to work with the BOSS is a SOSCHE ID#: GM1583B which worked perfectly.  There is also another wire harness needed to connect your steering wheel to the radio which is called a PAC ID#: SWIRC.  If there is a NEXT time, I'll do research in depth.  Good Luck