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B and W Companion 5th Wheel Underbed Kit Installation - 2021 GMC Sierra 2500

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How to Install the B and W Companion 5th Wheel Underbed Kit on a 2021 GMC Sierra 2500

Hey everybody, how's it going Today, we're gonna be going over and show you how to install the B&W Turnover Ball Gooseneck Trailer Hitch here in our 2021 GMC Sierra 2500. So the B&W Turnover Ball is a gooseneck trailer hitch. It has a 2 and 5/16 inch hitch ball, which is gonna be accommodating for most few snack trailers. However, a lot of people actually use this underbed installation kit to tow a fifth wheel. You are able to do this by using one of B&W's companion fifth wheel trailer hitches, that simply installs into the center square post here. It's available in both a fixed and sliding version.

So, no matter if we have gooseneck or fifth wheel trailers, we're gonna be covered here with the B&W turnover ball. So, there are a few reasons that I really like to B&W turnover ball. One of them is obviously the fifth wheel trailer compatibility. The other one is gonna be a clean, simple installation look. As we can see now, this is what it's gonna look like when we're telling a gooseneck trailer.

The only thing we're really gonna able to see is obviously the hitch ball, and we have the two safety chain loops here on the side, but when we're not towing, we can actually flip this hitch ball around, and store it upside down into the gooseneck hitch here, then, we'll have a pretty much uninterrupted truck bed here. So we're not gonna have to worry about taking up any space. We're gonna have still tons of room to do, and carry anything we need. So, we're gonna want to disengage our latch pin on the side of the truck, but then we can pull our ball out, flip it around, and then now we have it in the stowed position. So, if you're looking to get into fifth wheel or gooseneck towing, you may or may not already familiar with the B&W brand, but if you're not, what you're gonna come to find out is, B&W is one of the most highly rated options on the market.

They're very well reviewed and it's for good reason. Most of their products are completely overbuilt, they're built with very sick steel. You don't have to worry about anything breaking down, they're extremely durable. It's also all powder-coated. They have that signature gray powder coat which I really like.

It's gonna protect everything from rust, and with B&W, everything is made right here in the USA and it all has a lifetime warranty. So, in regards to weight capacity, you really shouldn't have any concerns at all. While we're using it with the hitch ball that comes with it as a gooseneck configuration, we're gonna have a 30,000 pound gross trailer weight rating, which is the amount of our fully loaded trailer. And then we're gonna have a 7,500 pound tongue weight rating, or rather pin weight rating, which is gonna be the downward force on the hitch ball. Now, if we're using this any fifth wheel configuration, with the B&W companion fifth wheel hitch, that's gonna limit us to 20,000 pounds, which is still gonna be plenty for most trailers. So if we come over here inside the driver wheel well, we're gonna show you the latching mechanism. This is what secures the hitch ball, or a fifth wheel hitch in the truck bed here. We're gonna simply pull out, and then rotate it to lock it in place. Now, we can flip our hitch ball upside down, or remove it, install our fifth wheel hitch. And then once we have it secured, it's as simple as twisting it and then letting it retract back in. So, in regards to installation, I will level with you guys, I've installed quite a few fifth wheel and gooseneck hitches, and they're not particularly easy. They are definitely gonna take you some time but I was pleasantly surprised with this kit here. It wasn't too bad at all. It really didn't take us that much time. We didn't really need any specialized tools. It was all pretty straight forward. I would definitely say, this is one of the easier gooseneck hitches I've installed. So, if you guys just have some basic tools and an afternoon to be able to do this, I do think you guys can do it at home by yourselves. Let's go ahead and jump into the install now so we can show you how. So, the first step of our installation today, we actually need to go ahead and lower the spare tire here. In order to do that, we're gonna be using a special tool that we have. However, the tools you need to lower the spare tire are gonna be included with your vehicle. So now that we have our spare tire out of the way, we're gonna be removing our spare tire heat shield. There's gonna be two bolts holding it in, one back here, one back here. We'll remove these bolts with a 13 millimeter socket. And we can go ahead and set this up, set this aside, we will be reinstalling it later. So now that we have the spare tire heat shield out of the way, there's one more heat shield we need to remove, which is this one over here above the exhaust. So we're gonna have four bolts. They're gonna be on top of the heat shield here. We'll remove these using the same 13 millimeter socket is before. If you have a ratchet with an adjustable head, it's gonna make things a little bit easier, 'cause it is a little tight up there. So, we're gonna have one final bolt for our heat shield. It's kinda hard to get to, it's gonna be behind this little wheel well liner here. So we're actually gonna need to remove this, or rather peel it up, anyways. So we're just gonna go ahead and do it now, if you give us a little bit more room to get to that bolt. So I'm gonna take a T15 Torx bit, remove these three Torx screws here. So once we peel that liner back, we should see it right in here. That was all of our bolts removed. We can go ahead and pull our heat shield out. Keep in mind, we won't be reinstalling this. So the next part of our installation, we're gonna be drilling the four inch hole into our bed here. So the first thing we're gonna do is we're gonna take a couple measurements. The first measurement we're gonna be taking, we're gonna find the center rib here on our bed. And we're gonna measure from the end of the bed, to a point which is gonna be describing our instructions. It'll be different if you have a long or short bed, but we want to make sure that we have the tape measure nice and tight up against the back of the bed here. And then we're gonna be measuring forward. I'd also like to note that, if you have a spray-on bed liner which is what we have here in this truck, you want to add about an 8th of an inch to a 16th of an inch of thickness to your measurement. So, you can make sure you get it in the right place. So, once we have our measurement here, we're gonna have to take one more, and that's gonna be the distance left to right. So, the best way to do this is to actually, there's gonna be a little rip here, on the inside of our wheel wells. We're actually gonna be measuring from there to there. So we'll hold our tape measure in place, and then we'll measure to the other rib on the opposite side. And once we get that measurement, we're gonna divide that by two. And that's gonna let us know what the center point of our bed is. So then, the point where the center point intersects with our long point, that's gonna be where we're gonna drill our four inch hole. So once we have that marked, we can take our four inch hole saw. We can go ahead and drill that point out. So a little tip for you guys here, we have a piece of plywood, and we're gonna be using this to help us drill our hole, 'cause it's gonna stabilize our hole saw a little bit. It's gonna have a lesser chance of jumping around on us. So I'll show you how to do that. So now we're gonna stand on our plywood here, and this is gonna help brace us. We also want to make sure that we have a nice tight grip on our drill here. 'Cause when it catches a drill that can kick and hurt her wrist. So let's just go ahead and drill our hole now. So once we have our hole drilled, I'm gonna come back with a metal file here. I'm just gonna clean up all the edges here. That way we don't have any sharp spots. Now, we're gonna go ahead and just clean up all of our metal shavings here. So now, finally, we're gonna come back with a paint marker. If you have any sort of clear coat spray paint that'll work as well, but basically, we just want to clean up all that bare metals. We don't have to worry about any rust issues down the line. So if you remember a little bit ago over there on the passenger side, we removed these Torx screws so we can peel back the liner. We need to go ahead and do that on the driver's side now, as well. And then we'll just peel back the liner here. Just like that. So now, we're gonna come back under the truck here. No, it doesn't matter if we're on the driver or passenger side. The passenger side is a little bit clearer so they can show you what's going on a little bit better but essentially, we're gonna have some welded nuts in the top of our frame here, we're gonna have two over here, and then two in the front, and it will be the same on the other side. So, these Walden nuts in our frame here are actually what we're gonna use to attach some of our rails for our hitch. We want to go ahead and make sure we clean those out first. So I'm gonna be taking a spray lubricant and spraying those down in those holes as best as you can. And then I'm gonna take a wire brush here. We're just gonna clean those out as best as we can. So then we're just gonna repeat that same process for the other two weld nuts up in here, as well as on the other side of the vehicle. So once we have the holes cleaned out, an extra step here sort of optional, we're gonna use this. That's gonna help us a little bit better when we're aligning all our rails. But basically, I'm gonna take my finger, I'm gonna fuel for that hole. And I'm gonna come straight down to the inside of the frame here where that is. I'm gonna take a paint marker. I'm gonna make a mark. So I know where that weld led is. And again, I'll just repeat that same process on our other holes. So now, we're ready to do a little bit of assembly outside the vehicle here. We're gonna take one of our cross tubes. We're gonna look inside, we're gonna notice that one side has this welded seam. We want to make note of that for this next step. It needs to be facing down. And then we're gonna take one of our cross member brackets here, and just simply slide that on like so. Then we're gonna take our hex bolts here that come in our kit. We're gonna line up our holes, and then we're gonna insert those through. And in the other side here, we have our flange nuts. We'll go ahead and install these and tighten them. So now, we're gonna take a 15/16 in socket and wrench. We're just gonna snug everything down. Now we'll come back with our torque wrench here, and torque it to spec. So a quick note here, we want to make sure that our cross tube here is gonna be flushed to the bottom of the plate on our bracket here. So it's not a perfect straight line because there's a little bit of an indentation here in the center, but it is touching on the two outside edges of which is what we're looking for. So now, we'll take our partially assembled crossbar assembly. I'm gonna take the end here without the bracket on it, and I'm gonna install it, or rather position it over the exhaust here, pointing towards the passenger side. So now that we have the opened end of our cross tube pushed all the way back, we want it to pretty much be sitting on top of our shock mount here. We're gonna take the other end with the bracket. We're gonna come up and over our brake lines here. So once we get up over the bracket here, you're gonna fight with it a little bit, because we have this wiring harness here, but, after adjusting our cross tube a little bit, we we're able to work it over the wiring harness, and then onto the frame, which you can see here. Now, we're just gonna push it all the way over to the frame, to give us some more room to install our other bracket here on the end of the cross tube. So now, we're gonna take one of our other cross tube brackets, and we're gonna slide it up in between the exhaust and our frame rail here. We hopefully get it into position on the rail. So I'll be honest with you guys here, we did have to fight with this one a little bit. It's not gonna be as easy as it may seem, but, we actually went ahead and lowered our exhaust here. There's gonna be a couple hangers here. We have one at the rear, and then two at the center which you can see here. I initially didn't think we we're gonna have to lower the exhaust, but, it definitely did make things a little bit easier. So, if you just remove those three hangers here, it's gonna make our lives much easier. So once we have the bracket into position, we'll go ahead and line everything up, and then we can take our bolt, and place it through to line everything up. On the backside here, we'll come back with our flange nuts. So now, we're pretty much gonna repeat the same process here for the rear cross member, again by attaching one of the brackets here first to the cross tube, putting it on the vehicle, and then placing the other one on. The only difference is gonna be, we're actually not gonna be torquing down this bracket here like we did for the other one. So the next thing we're gonna do is, we're gonna stall the latching mechanism onto our center section. Now, there are a couple of different ways you can do this, because one thing if you go on this side, working on this side, it's really gonna pin if you have a long or short bed truck. Our particular truck here is a short bed. Therefore, what we're gonna do is we're gonna position the center section here. So, they cut out for our bed channel is gonna be facing the cab. And then, since we want the latching pin to be on the driver's side, we're gonna come over here to this side of our center section, insert the latching mechanism like so. Then, we're gonna come back here with our carriage bolts, and our flange nuts that come in our kit. We'll go ahead and secure everything together. Once we have our nuts started, we'll come back with a half inch socket here. We'll go ahead and tighten those down. So now we're gonna get ready to set our center section into position. The first step before we do that, though, we're gonna take these long rectangular brackets that come in our kit here. I'm gonna place them on our cross tube peer on the front side of the cross tube, lining up our holes, and then inserting our bolts. So we're gonna do this for both the front, and the rear cross street. So now we're gonna go ahead and spread apart our two cross sections here. Not all the way just enough so we can get the center section in position. So now we'll take our center section here just again verifying that we have the latching release mechanism over here on the driver's side. Let's go ahead and set this up into position now between our brackets. Now we'll take our plans notes here, and just loosely secure the center section to our two cross sections. So the next thing we need to do, we have sort of an eye contraption set up. B&W actually offers a lifting device specifically for this purpose, but, if you don't want to spend the extra money, and you have a two by four laying around with some Jack stands or some blocks of wood, ideally, if you had a two by four, that was long enough, you could just set it across the bed rails here. But essentially, what we're doing is, we're trying to pull this intersection up, flush against the bottom of the bed here. So to make sure it's nice and tight. So once we have two support devices, we're just using some Jack stands in a two by four here, we're just gonna take a ratchet strap. And we're just gonna pull up that center section to get it nice and tight on the bottom of the bed. The next thing we're gonna do is we're gonna take our in 14 bolts that come in our kit here, and you remember cleaning out the wellness, and the frame earlier. So at this time, we're actually gonna secure these brackets that are attached to our cross tube til' the welded nuts inside our frame here using our provided bolts. So it's gonna be a little bit hard to see or get to. If you're on the outside of the vehicle, it might make it a little bit easier, or you can come up and underneath like we're doing now. So, we want to make sure that we're just tightening all these bolts by hand. Now, we're not gonna be torquing anything down yet. We wanna get them all in place first. Now, we're just gonna repeat this process of installing our bolts to attach the two brackets to our frame here. It is gonna be a little bit easier to come on the outside here, for the front wheels rail. So, we just peel our wheel well liner back, and then we can slide our bolts through. You want to make sure that you're careful not to cross threads so he should just be tightening them by hand until you get to the point where you need a wrench here, but again, you're not putting a lot of tension on it. You can still feel that it's threading in pretty easily. So now, once we have everything in place, we can go ahead and tighten and torque all of our fasteners using the sequence and specifications in our instructions. And so now it's time to install our latch release mechanism. Now, chances are, you're probably gonna need to pull this out and lock it into place just to give us a little bit more room to work, but, we're gonna take our handle here. You're gonna slide it up over the frame. Then we're gonna line it up with a square hole there, on our bracket, and then we'll secure it with our flange nut. Once we get it started, we can take our half inch socket and tighten that down. Make sure we don't go too tight. So now we're gonna come to the outside of the vehicle here where our fender liner is. If we peel this back, we'll see there's our at least handle. So it's pretty much gonna line up about what this little mounting tab here, pull it out. We also need to have room to lock it in place. So, what we're gonna do now is we do have some measurements in our instructions if you want to be exact, but, I really don't think we need to be that precise with this. I'm just gonna take out an area here, about like a square. So, I'm just using some tin snips for this, really, you could be able to cut this stuff with scissors. Little come over a few inches and I'm gonna go right below that mounting point there. So it looks like we got a little bit more cutting to do, have to cut up a little bit further, but we still want to make sure that we maintain that hole there so we can attach the fender liner. So the next thing we need to do, we're gonna come underneath the vehicle here. We're gonna get in the center section here. We're gonna see we have four holes, two on each side. The other two are a little bit harder to see, but, these are gonna be for our safety chain U bolts that we have in our kit here, we need to go ahead and drill these holes out to their final size of 11/16 of an inch, which is admittedly a pretty big drill bit. So what we're gonna do, we're gonna come underneath first. I'm just gonna come with a smaller drill bit. It doesn't matter what you get, and we're gonna just contort a drill out the center of the hole here. That's gonna give us our pilot hole. We're gonna drill that all the way through on these four holes. And then we're gonna come up top with a step drill bit, we're gonna enlarge them to their final size. Now, the only thing you really want to be careful of when you're doing this is that you're getting the center of the hole here with your pilot. Now we'll just simply repeat that for other three holes here. So now that you can see, we have our four pilot holes, two on each side, we're gonna come back with our step drill bit and we're gonna enlarge them to their final size. So, we'll just take a little bit out, test fit our bolt, keep doing that. It looks like we're almost there. Just need to remove a little bit more metal. So there we go. Now I'll go ahead and just repeat the same process for the other two holes. And then once we get them drilled, similar to how we did with the larger hole here, we'll take our vacuum. We'll go ahead and clean up all those shavings. And then we'll use a paint marker to fill in that hole there so we don't have any bare metal. So now that we have our holes drilled, we have our U bolts in place. We're gonna come up underneath, take our spring here, place that on. And then we're gonna have a nut here, we need to thread on as well. So we're just gonna be tightening this nut, until the bolt is gonna be flushed with the face of the nut. We're gonna be using a 24 millimeter socket to tighten that down. And now our final step here, once we have everything into position, we'll go ahead and just button up all the stuff that we removed earlier, such as the spare tire, the spare tire heat shield, and then don't forget to re-secure our fabric in the wheel wells. And that's gonna do it today for our look and installation of the B&W Turnover Ball Gooseneck Trailer Hitch, here on our 2021 GMC Sierra 2500..

Info for this part was:

Employee Jeff D
Installed by:
Jeff D
Employee Joshua S
Video Edited:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Chris R
Video Edited:
Chris R
Employee Zach D
Video by:
Zach D
Employee Jonathan Y
Video by:
Jonathan Y
Employee Jacob H
Video by:
Jacob H
Employee Shane H
Test Fit:
Shane H
Employee Conner L
Test Fit:
Conner L
Employee David F
Test Fit:
David F
Employee Ryan G
Test Fit:
Ryan G
Employee Thomas T
Test Fit:
Thomas T

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