fifth wheel install

[partsman01]

So bought a used hijacker slider hitch, to replace my very old hijacker UL-16, my question is how many bolts do you use to hold bracked to frame, previous owner only used one, and truck I looked at here at work only used one hole to attach bracket to frame.
I thought one had to use two minimum, plus it looks like the original fellow also started his bracket from the second hole, and I thought it was supposed to be first hole used then two more on each side?

[RustyJC]

On something this critical, I suggest you look HERE to see if the information you need is available. If not, phone numbers are provided at the top of the linked page to contact the manufacturer.

Rusty

[K-Star]

I agree with Rusty. Go with the recommendation of the manufacturer. This is much too critical of a decision to be made any other way.

[wittmeba]

Gotta agree with Rusty too. But I will tell you that per the instructions from Reese for my 16K:

Each rail has 4 bolts holding the rail in the truck bed.

There are 2 bolts per bracket holding the bracket to the frame of the truck.

There is 1 bolt each end holding the bed rail to the bracket and 1 bolt each end holding the bedrail to the truck bed.

Summary: there are 8 bolts holding the brackets to the truck frame and 8 bolts holding the rails to the brackets and truck bed.

[partsman01]

I don't think previous owner followed instructions, due to only one hole in the frame and it does not seem to be in the right place for the brackets for the fifth wheel, so will have to see what the other brackets are like, as I need four 411 and two 411C brackets for the GMC.

[Ray,IN]

Obtaining the vehicle specific installation instructions is vital. GM uses a hydro-formed frame, drilling holes in the wrong place may severely weaken its structural strength.

[K-Star]

depending on the year of your truck, the holes may be predrilled. Back as far as my first 5er hitch (1999 Ford F-250), the holes were already in the frame. Or maybe Reese designed their system to use holes that would already be there. Either way, no drilling was involved. Same held true for my `02 GMC, `06 F-350 and `08 F-450

[partsman01]

So bought this used 96 GMC long box, extended cab 4x4 K2500 from a dealer, and the fellow that had it had a sliding fifth wheel hitch in it at one point, but does not appear he followed any directions, rails on a used hitch I picked up do match for the shape and holes he drilled, but does not sit according to Hijacker instructions, and he only had one bolt per bracket, although he did use four brackets, maybe to compensate for it.
Anyway thought I would post pics to show how it sits now, not bolted in, I just placed the bolts in, had to redrill two holes on one side as the hitch was not sitting square at all.
Tried to show how it sits, how in forward position it is a bit ahead of axle, other picture is second position to show it is the middle of axle, it would appear if the rails had been put in at the spacing Hijacker states, it would only ever come to the middle of the axle at most, maybe why the fellow set it further up.
The other thing he did is the spring loaded pins that drop down into the slide he drilled right through the bottom of the box bed, I don't think that was supposed to be done.
Any feedback on this set up?
I had told one poster here I would post pics for him to see.
First to show hitch sitting in place, not bolted.


Second showing the forward most position.

Third showing second setting from front most position.

Showing where bolts come through, close to holes he drilled and factory frame holes, no brackets attached yet.

Tried to show how far it is from back of box, not what is called for.