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Custom Underbed Installation Kit for B&W Companion 5th Wheel Trailer Hitches

Custom Underbed Installation Kit for B&W Companion 5th Wheel Trailer Hitches

Item # BWGNRK1057-5W
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Fifth Wheel Installation Kit

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B and W Below the Bed Fifth Wheel Installation Kit - BWGNRK1057-5W
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Install a Companion fifth-wheel hitch in your truck bed with this custom kit. Better than a traditional mounting kit, this setup doubles as a gooseneck hitch when the fifth wheel is removed, and the underbed design allows for full bed access. 1-833-496-1390 to order B and W fifth wheel installation kit part number BWGNRK1057-5W or order online at Free expert support on all B and W products. Guaranteed Lowest Price and Fastest Shipping for Custom Underbed Installation Kit for B&W Companion 5th Wheel Trailer Hitches. Fifth Wheel Installation Kit reviews from real customers.
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B and W Fifth Wheel Installation Kit - BWGNRK1057-5W

  • Below the Bed
  • Custom
  • B and W

Install a Companion fifth-wheel hitch in your truck bed with this custom kit. Better than a traditional mounting kit, this setup doubles as a gooseneck hitch when the fifth wheel is removed, and the underbed design allows for full bed access.


  • Lets you install your B&W Companion 5th wheel trailer hitch (BWRVK3500 or BWRVK3400)
  • Doubles as heavy-duty Turnoverball gooseneck trailer hitch
    • Includes rails, gooseneck hitch head, safety chain loops, and hitch ball
  • Provides complete truck bed access when you're not towing
    • Single hole in center of bed is mounting point for hitch
  • Installs easily using existing holes in your vehicle's frame
    • No welding or frame drilling required
    • Truck bed does not have to be removed
    • 4" Diameter hole must be cut into bed
  • Powder coated steel is sturdy and corrosion resistant
  • Made in the USA
  • Limited lifetime warranty

B&W Turnoverball Gooseneck Trailer Hitch

B&W Turnoverball Gooseneck Hitch

Not only does this kit provide you with a sturdy, custom base for installing your Companion fifth-wheel trailer hitch in the bed of your truck, but it also doubles as one of the most recognizable gooseneck hitches on the market. This fifth wheel installation kit actually is the Turnoverball gooseneck hitch from B&W.

Gooseneck Specs:

  • Gross towing weight: 30,000 lbs
  • Vertical load limit: 7,500 lbs
  • Ball size: 2-5/16"

B&W Companion Installed in Turnoverball Gooseneck Hitch

With the B&W Turnoverball underbed gooseneck trailer hitch you get the best of both worlds. When you go to tow a gooseneck trailer, the Turnoverball creates a sturdy, dependable connection with your trailer. And when you're done towing, you can stow the ball upside down in the hitch to get full bed access and a clean appearance. When you're ready to tow your fifth wheel trailer, just install the Companion in the ball hole in place of the gooseneck ball and lock the post in place using the built-in handle. You can remove the fifth wheel when you're done towing, leaving your truck bed open once again.

Simple, Custom Installation

This kit is custom designed for your vehicle. The mounting brackets bolt to existing holes in your truck's frame. While some modification is required - you will need to cut a 4" diameter hole in your bed for the hitch ball and drill holes for the built-in safety chain loops - there is no need to weld onto or to drill into your frame.

Once you have the brackets and center section installed, set up the operating handle. This handle is designed to be accessed from the rear driver's-side wheel well. On the end of the handle is the heavy-duty steel pin that secures the mounting post of the Companion (or the base of the gooseneck hitch ball).

GNRM1057 B and W Turn Over Ball Under-Bed Rail Kit

GNRC959 B and W Turn Over Ball Center Section

Installation Details BWGNRK1057-5W Installation instructions

This Product Fits The Following Vehicles

California residents: click here

Video of Custom Underbed Installation Kit for B&W Companion 5th Wheel Trailer Hitches

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for B and W Underbed 5th Wheel Trailer Hitch Installation - 2018 Chevrolet Silverado 1500

Today on our 2018 Chevrolet Silverado 1500, we're going to be taking a look at and I'm going to show you how to install the B&W underbed trailer hitch with custom installation kit. This fifth-wheel installation kit is designed to let you install your B&W companion fifth-wheel trailer hitches. The underbed design of this kit allows for full bed access and, when you are ready, it's under five minutes to convert your empty truck bed into a fifth-wheel hitch.We'll start off by unlocking our B&W hitch and installing our fifth-wheel adapter. We have ours preassembled, but you can adjust the uprights here depending on your truck and trailer combination. At this point, the hitch is ready to attach to your trailer. There's a little clip here that you release.

Basically, it's a safety pin. Then you swing the handle out and you can watch the jaws open. Now you're ready to back onto your trailer. Once you're secure on your trailer, you can reinstall the clip. And since this fifth-wheel installation kit doubles as a gooseneck hitch, when you're not towing your fifth wheel, you can remove it.

This frees up the hole to reinsert the hitch ball when you need it.Our center section is going to be completely under the bed of the truck. It's going to be secured with two cross members that span from frame rail to frame rail. We're going to have a frame bracket for each side. Our frame bracket attaches to our cross members, attaches to our frame, and attaches to a U-bolt that spans around the backside of the frame. All of our components here are going to be constructed of a steel, with a nice gray powder coat finish.

Now that we've gone over some of the features, let's show you how to get it installed.The first thing you're going to want to do is the lower your spare tire. After we remove our spare tire, while we're under the truck, we're going to go ahead and remove a section of our heat shield. Our hat channel runs right above our axle. We want to cut our heat shield right in front of it, all the way up to the next .. that channel.

We're going to cut right behind it, so we're cutting this center section out of our heat shield. And I'm just going to use tin snips. However you want to cut it. If you use anything that is electric, just remember your gas tank's right here. Just be aware of that.Now if you have any of this edge that's protruding past this hat channel, take a hammer and just flatten it out inaudible 00:02:21. And then do the same thing with the front, up here. The next thing we're going to do is we're going to lower our exhaust to help us when we put in our center section. Now, directions tell you to do this right before we go on to do our center section. It might be easier if you do this before you cut your heat shield out. It might make it a little bit easier to cut the section that's right over this bin here; completely up to you. Spray some lubricant on your hanger and just take a pry bar and pry it off the end of the post. You'll have three of them that we're going to do. We're going to do this one. You're going to have two right in front of the axle.In the bed of our truck, we need to mark it out so we can draw our 4" hole for our gooseneck. Now, you're going to measure per the instructions, per your bed sides. Keep in mind, if you have a drop-in bed liner, it's probably easier to take that out when drilling this hole. And if you have a spray-in bed liner, you also need to take into account that. Just follow the instructions on which bed liner you have. We're going to measure from the edge of the bed straight up the center, and we're going to put a mark. And I'm just using a paint marker. Once you find that mark per the instructions, you're going to measure between your wheel wells to find center. So then we're just going to split that number in half.Once you find your center, make your mark. 4" hole saw blade. So what I like to do, if you see my board here, if you take a piece of plywood and just drill a 4" hole in it, or a 4 1/8" hole . So when we're drilling with our hole saw bit, when it starts hitting that middle and grabbing on, it doesn't kick it all over the place, because this board's going to help keep it in a good circle. Another thing I suggest when doing this, don't just hold it with your hand, take it and set it up against the back of your leg, because if it grabs, it's going to kick this thing sideways and it can hurt you. Another thing, before you start drilling all the way through, just make sure there's nothing in that area that you're going to damage.It's a good idea to take a file and knock the burrs off that are around the inside of the hole. Clean up all of our shavings. I'm going to take some Rust-Oleum clear coat . If you have a black bed, black Rust-Oleum paint, anything, just to cover up that bare metal to reduce the risk of rust and corrosion later on. On our passenger side, if you have a fender liner, go ahead and remove it. Just held in place with a couple of screws that run along the inside here. Then this hat channel that runs over our rear axle, on the front side of it, we're going to measure from that edge up 6 1/2" and put a mark. That's going to be our center mark. We want a 1"-wide mark. 1/2" forward, 1/2" back gives us our 1", and then 1/2" up. So you can see how I have it in a triangle there. Now we're going to cut that piece out so we can slide our cross member in place. Just going to take a dremel tool, with the cutting blade on it.Now we'll take our front cross member, it looks like this, and make sure when we put it in that these holes are facing towards the back of the vehicle. This flat flange here is actually going to sit on the bottom of the bed. We're going to slide it right through, just like that. Now it's a good idea to go underneath the vehicle and slide it under the rest of the way so you don't damage any of your brake lines or anything in your fuel tank area. Turn your bar up like this, face your holes towards the back. In your kit, you're going to have a rubber O-ring. You're going to take your 1/2" x 1 1/2" bolt, and we're going to put it into this second hole. We're going to use the rubber O-ring to help secure the bolt in there. And it might be easier if you put it in before you flip that up, because it's hard to reach over that fuel tank. We're going to take it, and we're going to push it about 4" in front of our hole. We're stuck here with our shock mount, so we're just going to go ahead and push it all the way up to our shock mount, just like that.And then we'll install our rear cross member. Take your rear cross member, it's going to have threaded holes in it. Most of the time these are going to have to be cleaned out, because when they powder coat these, the powder coat gets down inside of there. Take your bolt that you're going to be using, it's your 1/2" x 1 1/2" bolt, and see if you can hand-thread it in. If you can't hand-thread it in there, then it needs to be cleaned out. This one is actually getting hung up. I'm going to clean it out anyway, even though I am getting it to go through. I don't want to take a chance of the threads crossing. A couple of ways to clean it out: use a tap to do it, or, if you don't have a tap, if you have a bolt that's the same size, just make sure the thread count's the same . Take the dremel tool, cut a few notches in it. One straight down like this, one and one, to give it some grooves, and then you can use that bolt to tap it out. Rear cross member, we're just going to slide it just like we did the front one. Get it about part of the way in there, and then go underneath the truck and slide it in the rest of the way.Make sure you watch here on our driver's side, you have your hard brake lines. We want to make sure we're not going to damage those, so just be careful when sliding this over. I'll go ahead and tell you now, the holes, if you noticed, they are closer to one side than the other. We want them to be towards the floor, so when we rotate it, we're going to rotate this side up, just like this, and we're going to go right up against this hat channel, like this. And it might be easier to get a pair of channel locks, grab that, and then pop it into place, which I think is what we're going to have to do. Just grab it like this, just like that. And again, watch your lines over there. We're going to push it all the way back up against our hat channel, just like that. Take your center section . You'll notice that the hole is more towards one side. That's going to be towards the back of the vehicle. We're going to line this up with the hole we have in the bed of the truck, go over our fuel tank. Get it lined up on that bolt.For the front of our center section, 1/2" x 1 1/2", and we're going to slide it through like this, and then we're going to do a lock washer and a nut. Do the same thing for that one, like that, and then our bolt up on top that we previously installed. We're going to do the same thing. Lock washer, and then our nut. For our back cross member and center section, 1/2" x 1 1/2" bolt, lock washer, and then a flat washer. And you can see how I have them installed here. Now a couple of things to have handy. You need a spacer block like this, a carriage bolt, retaining clip, and you're going to need this oval-shaped spacer with a hole in it.We're going to take our spacer block and our bolt, and we're going to go inside this hole right here. And we're going to do this on both sides of the vehicle, like that. And you want to rotate that clockwise so that the spacer block hits the bottom of the frame rail. What that's going to do is when we go to put on our nut, that allows the spacer block to catch, so have something to tighten onto it. Now we're going to take our oval-shaped spacer, and that is was going to actually take up that space in that hole, like that, and then we're just going to thread on the retaining clip. That's going to hold our bolt in place. inaudible 00:12:25 to make sure that that oval sleeve is lined up in the hole. Go ahead and get this retaining clip all the way up against there so it holds it in place. Then we're going to do that same thing on the other side.Now we'll install our side plates. You'll notice how our side plate looks. We want this section to be towards the front of the vehicle. This hole right here is going to go over this stud that we just installed in the frame rail. Put on a flat washer first, like that. Like that. And that. And then for this back hole in our cross member, we want to do the same thing that we did with all of our hardware in the back: our bolt, lock washer, flat washer. And then for our forward hole, take your hex bolt. We're going to go from the front into the center. So we'll pass it through our front cross member and then through our side plate. Then we're going to put on our flat washer, our lock washer, and then the nut. Then you're going to do that same thing on the other side.We're going to have a frame clamp that looks like this, one for each side. You notice that it has a notch cut out. That's going to go at the top. You'll notice this wiring here, it's clipped in. I'd take a flathead screwdriver and pop that loose, like that. That'll give us some room there. Take this, go up, like that. And we're going to have a hole here in our frame bracket, and then we'll have one at the top, also. We want to get those in those holes. And then for the threads, we're going to put on a lock washer and a nut.The next thing you want to do is you want to make sure you're centered, that the rails across members are pretty much in line equal distance from side to side. What I did is I got up in the bed and checked to see how our hitch center here is centered in the hole. It looked like it was pulled back just a little bit. So to start our tagging sequence, I'm going to start . We always start with the center section. I'm actually going to start by tightening this front one first, and pulling my hitch that way. We'll use a 3/4" socket and wrench. Once you have your center section tightened, then you're going to torque that hardware to the specifications in the instructions.Now we want to tighten and torque our U-bolts that are wrapped around the inside of our frame rail. We're going to make sure when tightening these down, you tighten them and torque them. Alternate back and forth. Don't just tighten one and torque it, and then do the other one, because then it gets off. So we go back and forth, do a couple of turns on one, a couple of turns on the other, until you get it up to the manufacturer recommendations on the torque specs. Next bolt you need to tighten and torque are the two bolts from your frame bracket going into your cross members. Once you tighten and torque those, this stud here is going to be the last one you tighten and torque.Now we're going to install our handle. It might be easier to go from the outside, in. You want it to go right through that slot, like that. Line it up with that square there. And we're going to have a small bolt like this small carriage bolt going from this side, through your handle, and you'll put a flange nut on the back. And then go ahead and tighten that down. Now we're going to drill out for our safety chain U-bolts. You're going to have four sets of holes on each side of your center section. So if you notice right here in our bed, how we have a raised section and then a lowered section, we want the holes that line up with our dropped section. So it looks like with this one, we're going to be using our two inside holes on each side. They're going to line up right here on this edge. So we're going to drill out the hole from the bottom. They tell you in the instructions to just drill it out to a 1/2". What I like to do is use a small drill bit, drill a pilot hole, and try to center it in there.And then go up top and use either a step bit or even a 1/2" drill bit if you want, and drill down from the top. It's a lot easier than trying to do it all from down here. Make sure you get any burrs off. What we want, is we want this. Make sure you go over it with some clear coat or paint, or whatever it is that you're using again. Go ahead and drop these in place. Underneath the vehicle, inaudible 00:18:46 U-bolt, you want to take this spring, your Christmas tree spring, make sure the larger end is up at the bottom of the hitch. We're going to slide it over the bolt, and then we're going to put on this lock nut. And we're going to do that on each one.3/4" socket. We're going to tighten these down. You'll notice the ones I've got tightened over here. We only want the head of the bolt, we want it to be flush with the edge of the lock nut. Just like that. On our driver's side, where our handle is . and you see our fender liner covers it a little bit. We're just going to cut out just a small square, to give us access to it. Now I'm just going to use a utility knife to do that. Once you get everything tightened and torqued down, go ahead and reinstall your exhaust. Reinstall your passenger's side fender liner, and your spare tire.That'll do it for the look at and installation on a B&W underbed trailer hitch with custom installation kit on our 2018 Chevrolet Silverado 1500.


See what our Experts say about this B and W Fifth Wheel Installation Kit

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    For your 2014 Chevrolet Silverado 1500 with the 6-1/2-foot bed there is a perfect solution to allow you to tow both goose neck and 5th wheel trailers. The ideal solution for your application is the B&W system. B&W designed their goose neck/5th wheel system so that the under-bed 5th wheel installation kit doubles as the goose neck hitch. This system consists of parts # BWRVK3400-5W and # BWGNRK1057-5W. Please note the 5th wheel hitch cannot be used with Sidewinder or Revolution pin boxes...
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  • Can B&W Companion be Used to 5th Wheel Tow with 15 Chevy Silervado 1500 with 5-1/2 Bed
    The Custom Underbed Installation Kit # BWGNRK1057-5W will fit your 2015 Chevy Silverado 1500 with the 5-1/2' bed and while you can technically use the Companion Slider # BWRVK3400-5W, it (and any other standard slider hitch) will not provide enough turning clearance for your trailer and 5th wheel trailer. Since you have a 5-1/2' bed you need something that will give you at least 22" of turning clearance and we do have a few options for you. The first option is to use the Demco 13K Autoslider...
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