Placement of 5th Wheel Rails for Reese Hitch # RP30051 in 2004 GMC Sierra 2500 LD 6-1/2-Ft Bed

Question:

What are the measurements from rear of box on a 2004 gmc 2500 Ld with 6.5 foot box crew cab to install a fifth wheel hitch? How far back do the front and rear rails go?

asked by: Darius

Expert Reply:

You have two options for installing your Reese # RP30051 5th Wheel Hitch in your 2004 GMC Sierra 2500 LD with 6-1/2-foot bed, either a universal install kit or a custom kit. Universal kits require you to drill into the truck frame and typically require about 5 hours for installation. Custom bracket kits require no frame drilling (but still require drilling through the bed) and install in about half that time. I recommend the custom install kit # RP50064-58 for your 2004 Sierra.

Please note that 5th wheel hitches cannot be installed over plastic bed liners, but spray-on liners are compatible. I have linked a video showing how to trim a liner in case this is required for your installation.
I have also attached the installation instructions for this kit; please note that the instructions include several different sections depending on the specific version of truck. Page 10 shows a bed rail placement diagram. I have also linked an installation video for this kit in a 2008 Sierra 2500 HD as well as a general article on installation tips.

For your 6-1/2-foot box, you will place the front rail so that its rear edge is 47-1/2-inches forward of the rear lip of the truck bed. You will then use the slider legs to determine the position the rear base rail.

expert reply by: Adam R