Fifth Wheel Rail Kit Recommendation for 2008 GMC Sierra

Question:

I am trying to find a way to make use of the gooseneck hitch installed in my truck used when I bought it. I did not come with a ball. Heres what I know: The hole for the shank is 3/76mm in diameter, 3.5/89mm deep, and it is keyed at 12:00 perpendicluar to the pin. The key is 10mm wide and 7mm deep. The pin size is 0.65/16mm and the top of the pin is 1.4/36mm from the top of the shank hole. The pin is about 46.5inch from the rear of the bed give or take 1/8. The cross arms are 7inch apart measured from the inside edge which indicates a 7inch plate/head. The side plates are 24inch long on each side of the frame rails. I didnt get the plate length but there appears to be 8-1/2inch bolts holding the plate to the cross arms. I have not been able to find a ball for this hitch so I am reaching out. Id ideally like to find a ball but if I need to, the next option is to see if a new plate will mount to my cross arms. Another option would be to find some fifth wheel rails to mount to my current equipment. The end goal is to tow a fifth wheel camper and not drill any more holes in the bed of my truck. Thanks!

asked by: Mike

Expert Reply:

If the picture you submitted is the gooseneck hole you have in the bed of your truck we aren't going to have a ball that's going to fit it and work well. Only solution we'd have would be for you to remove the underbed hitch and go with a set of custom install fifth wheel rails like the # RP50064-58 which will minimize drilling and install time for your 2008 GMC Sierra.

Then you'll be able to use a fifth wheel hitch like the Reese part # RP30047.

expert reply by: Jameson C