Rusty Rotted Rocker How to Replace a Truck Rocker Panel

Oh, that's horrible. In this video, we're gonna be fixing this rust.

So, if you have a vehicle that's over 10-years-old, and you live in an area where they use a lot of salt on the roads, like here in New England, you're probably gonna end up with rust like this. And there's not much you can do other than...just break it up. This panel, this whole panel has to be replaced. You can't just patch this up a little bit.

Now, while we're replacing this panel, I'm gonna have the doors off and this running board out of the way. This panel right here is rotted pretty bad too, so we're gonna replace that also.

First thing I'm gonna do is remove these running boards. I'm gonna do that by removing some bolts on the back side.

There you go.

Now we remove the running boards so those are out of the way. The next step I need to remove the door, so I'm gonna start by disconnecting the electrical connectors and then get the hinges off and then do the same for the front door.

Now we got those doors off, now I'm gonna take this panel off. I'm just gonna use the trim tool and pop it out.

There you go. Now I have to get the weather stripping out of the way. I'm gonna take this trim piece off, pull that up, and do that on the front as well.

Now before I cut back any of this metal, what I'm gonna do is just take my new panel and just hold it up where it's gonna go. And I can just take a marker...now it's not gonna be perfect, but you can, at least, get an idea and just trace it.

And if you only had rust on the back side, you could cut this panel in half and just do the back or just do the front.

To start, I am gonna cut back a little bit further from the line. I don't wanna cut right up to the line. In case I cut too much off, you can always trim it back a little bit more. So we'll do that now.

So, if you're using a cutoff wheel or a grinder, you wanna keep in mind where the sparks are going. You don't want them getting into the carpet potentially catching the carpet on fire. Now they make special spot-weld drill bits that you can put on the end of your drill, and it's kind of like a hole saw, it just cuts around the spot weld. And then you can pry this off. If you don't have one of those, so what you can do is take a smaller drill bit. Just drill right in the center there a little bit. And then, once you get it started, you don't have to go all the way through. It's ideal if you don't go all the way through. Then take a bigger drill bit and just drill right there, until it looks like this. And, as you're doing this, have your chisel and just hammer it and you should be able to break it. And you have to do this to all of these on both sides. It's a lot of work, it's a little bit tedious, but it's not too bad.

Grab the panel and just slide it out. Just bend it down just like that. And it's still attached down below. This is pretty rusty down here.

Now, if this panel underneath here was in better condition, you would have to do the same to those spot welds underneath there, drill them out and just pry them down. Because it's in such poor condition, I'm just gonna use an air chisel and chisel it off.

There it is. All right, so I got the old one trimmed out, and I'll just slide the new panel in place. And it fits pretty good. But before I make my lines to trim it out a little more accurately in the front, it doesn't fit here too well, so I'm just gonna trim this back a little bit, get this to line up good, and then I can make those lines.

All right. So I trimmed up some of the underneath here and grinded it down a little bit. There is a little bit of rust right there, I will have to treat that rust a little bit, before I weld this up. But at this point, I just wanna line this up again, just get an idea of how it looks. It looks good underneath. Now I am gonna just trim this front part first, get this to line up. And then, once that's lined up and looks good, we'll start trimming the rest of it.

All right. So I cut this side out right here, that lines up really good. Just like that. I might have to adjust it a little bit. But overall it looks really good right there. Now I can continue on the other parts and do the same.

All right, so that's all trimmed up, all the areas are trimmed. It looks pretty good. Just like that. Now we can start prepping this panel and this area, so that we can weld it on.

So where the spot welds were, if there's anything that's raised up, you just trim it down. Make sure it looks good. And then same with underneath here. There is some rust here. If you want, you can sandblast that or use the grinder. And then underneath here as well. Clean that all up. All right, in these areas, I'm just gonna take some acetone cleaner and a rag and just wipe it down. All right. Now any bare metal, you wanna take some primer and just give it a couple coats. And then, right here, do the same.

Now that primer's dry, I'm just gonna take a little bit of spray paint. It doesn't necessarily have to be the exact same color as the car, this is just gonna prevent the rust. And just spray it on...and you could give it a couple coats.

Now, the reason why I use spray paint and not rubberized undercoating; a lot of times rubberized undercoating is flammable. And when we weld, you could potentially have a fire in there and not even notice.

Now we're gonna start prepping the panel. Any of the areas where we're gonna weld, I'm going to use a grinder and just grind the surface.

Now that we have those areas cleaned up, I'm gonna drill some spot-weld's holes. I'm gonna take a smaller drill bit and just go along right here, just put a piece of wood underneath there. And I'll drill them a little bit bigger after. And then go about 2-inches apart or 1.5 inch. They don't have to be in the exact spots where they were originally.

And then we're gonna do the same on the bottom right here.

So I have all those holes started. And now I'm just gonna go back with the drill bit with a 5/16 drill bit and just make those holes bigger. Now, if you have a specific spot welder, you wouldn't have to do this step, but we don't, we're just gonna use a MIG welder. Start those.

So, I have all this area cleaned up with the grinder. Now, near each hole, I actually have to clean up. I don't have to clean this whole thing up but I could just do at each individual hole. Just like that. And I'll just do all those on both sides.

And now the body's all set. This is all cleaned up, this area. I did end up grinding this area down, even though we just painted it. I didn't really need to paint that at the time. So that's cleaned up because the spot welds we're gonna weld right to there. Just get it lined up.

And I'm gonna take some locking pliers. Just get that locked on right there.

And right there. Looks good. All right, so this looks pretty good. This is lined up, my gaps look pretty good over there. And you're gonna wanna clamp from underneath as well.

Now I'm gonna go around and fill these spot welds. I did protect the carpet with a welding apron and a damp towel. And I'm gonna do some tack welds in this area. I'm not gonna put a straight bead because you could potentially warp the metal. I'll just do small tack welds, a little at a time, and just go back and forth. And I'm gonna move the locking pliers to each tack weld as I do it. Let's see.

All right. All right, so that looks pretty good. I am gonna fill this in a little bit more but, before I do that, I'm gonna do the same thing with the spot welds to the bottom. Just clamp these down and just go in between each one one at a time.

So this came out pretty good. I happen to be using a flux-core welder, that's why you see all this mess. I can just take a wire brush, just clean this up a bit. And then, if I have to, I can go back. If you see any holes that you don't wanna leave, you can go back and fill in some of those holes. Do it a little bit better. So... I'll clean this all up, and then I will take a grinder and just lightly grind it down a little bit. We're gonna use a little body filler in this area and this area and the area where the spot welds are. If you find you have to go back and re-weld it a little bit, that's okay. Those look pretty good though.

Now, I don't wanna grind it down too much. What you can do is just take the body hammer and just hammer it down a little bit.

So I got this all grinded down good and that looks good right there. And where the spot welds are, those are all good. I'm not gonna put any body filler on here yet because we have to replace this panel. So I'm gonna do the same thing over here as what we did here. Just slide this in position and just make a mark. And I'll just cut a little bit below this. And then same with the little spot welds. I'm just gonna have to take the drill and drill those out on here and then on the back side as well.

I couldn't access these spot welds down below, so I pulled the tire off to just gain access. Now I can drill these out.

Now those are all drilled out. Now I'm going to take a screwdriver or a pry bar and try to pry this panel up.

I'm gonna take my panel with that off and just line it back up. Let's see how it's supposed to fit. Looks pretty good. Okay, so I can trim this back a little bit more. It's better to keep trimming than to trim too much off. So I'll just trim up to that line and see how that looks.

There's this foam insulation right here. I'm gonna take this off. It's probably not flammable, but just in case it is, when I'm welding, I don't wanna create a fire, so I'm just gonna pull this off get it out of the way. Most likely, it's just for sound deadening. So I'll just take some of that out of the way as well.

So this panel fits pretty good here. So now I'm just gonna prep the surfaces and get ready to install it.

All right. Now I'm gonna line this up and map out where I wanna drill the holes. And I just need to remember that area and that area. I don't have to drill anything, so I can drill one about every 2 inches. And then, same as the other panel, just drill these holes. I'll start with a smaller drill bit first.

Now I'm gonna use the grinder and clean up all around all these holes. And this area we're gonna weld to the body.

Now I'll take the panel and line this up. That looks good. And take some locking pliers [inaudible 00:23:43] area on the side and lock it into place. I might have to adjust it a little bit.

I'm gonna start by tack welding the top part, make sure that's in there good. And then I'm gonna have to readjust the sides.

I'm gonna clean up this weld with the grinder. I'm not gonna grind it down too much, just take a hammer and tap it down a little bit, this stuff, if you wanna get that pretty even. And then, I can go back with the welder and see if there's any spots that I missed, if there's a major gap.

So I grinded down the welds and they look pretty good. What I wanna do is just take a straight edge or a ruler and just make sure the welds are not touching any part of the ruler. Make sure there's a gap there. I'm gonna use some body filler. And that looks pretty good. But if the welds touched the ruler, you're not gonna be able to grind that down more, once you have body filler on there. So what you can do is just take your hammer, like I said before, and just tap it down. It looks pretty good.

I'm just gonna use a little cleaner or some acetone and a rag. Just wipe this down in any area you're gonna put body filler. It's good. Do the same for the rest of it.

Now I'm gonna mix some of the fiberglass body filler. What I wanna do is take a piece of cardboard and some plastic and just tape it to the cardboard, just so you have a nice area to work. Take some of the body filler, you're gonna mix that up. Just put some right here. And you don't wanna mix too much, it should be about...about a 3-inch diameter circle between 0.25 and 0.5-inch thick. That looks pretty good. And then, we're gonna have the hardener. You wanna open the bottle of hardener. Just squeeze the air out and close the cap. And just mix it up. Just squeeze it. Shake it a little bit. And you wanna follow the directions on the bottle, but pretty much most of them are the same. And then just squeeze about that much hardener on just a line across. It should be good.

Now you bring it over to the vehicle that you're working on, before you start mixing. Because, once you start mixing, it's going to harden up pretty quick, you don't have much time to work with it. So just try to mix it together so it's all one color trying not to get air bubbles in it.

All right, so I'll just take a little bit and just spread it. You wanna really push it into the welds. And this is the base coat, this is gonna go on the bare metal and it's gonna give you strength and it's gonna seal. And I'm gonna do the same with the rest of it. Looks pretty good.

I put up some plastic just to prevent some of the dust from getting into the car as I'm sanding. The dust gets everywhere, so make sure you put up some plastic. Okay, now you don't wanna wait too long before you start sanding because, if you wait too long, this stuff turns very hard, and it's a lot harder to sand. So you gotta check it. I'm gonna use some pretty coarse sandpaper, some 40-grit or 36-grit sandpaper. And when you're sanding, use a sanding block. You're gonna wanna go in all directions, go up and down, back and forth. And then a lot of crossing, if you do Xs, that helps out a lot.

So if you started doing this and it's still a little tacky, then you might have to wait a little bit longer. But this is perfect right now.

So this is coming out pretty good, so I can switch to an 80-grit sandpaper to get some of these lines out. It is important to use a sanding block when you're doing this, you don't wanna just take the sandpaper and use your hands because you're gonna get finger marks in it. And it won't be as smooth, it'll take a lot longer. So I'll switch to 80 grit and just do the same thing.

So with this body filler with the fiberglass in it, I have the right shape that I need. Now I'm gonna use another type of body filler that's just gonna fill in any of the imperfections. I'm gonna do a real thin coat of this. The filler that's on there, there wasn't a lot of filler on there as it is, it was a pretty thin coat. And so, I'm just gonna mix this up the same way. I probably mixed up a little too much here.

Okay, that's mixed in pretty good. Now just spread it nice and thin. The thinner you spread it and, the more even you spread it, the less you have to sand.

As you're doing it, you'll notice that it starts acting weird, then you know it's actually all done. It's too hard, so you're gonna have to mix up some more if you need more. And then, when you're done, just take your squeegee and just push it like that and just let it harden right there. It's easier to peel this stuff off when it's hard.

All right, so we let that sit about 10 minutes, just follow the directions on the can. Now I'm gonna sand it with a lighter grit sandpaper, I'm going to 180. Like I said before, I already have the shape I need, now I just wanna smooth it out.

Now, that came out pretty good. Now I'm gonna use a DA sander with 220-grit sandpaper. Now, this DA doesn't spin, it kind of orbits, so it's a little bit safer to use. And I'm just gonna try to feather it in just so it smoothens out a little bit more.

So this is nice and smooth now, and I cleaned this area up, wiped it down with a sponge and some water, cleaned it up. And any area where you're gonna paint or even use the primer, you're gonna wanna scuff up the paint. You can use a scuff pad and just try to scuff it up, just a non-abrasive scuff pad. Now, when I mask off this area, I don't wanna put a line right there, a piece of tape, because then you're gonna have a line that's gonna show. So, what I'm gonna do is go up a little bit higher, just put a piece of tape here, this tape here. We can fold this over just like that. Then I can put some plastic on the top. Then, when you're spraying, just try to spray in the down direction, you don't want it spraying up there. You will get some overspray in that area but, at least, there won't be a solid line.

And now, on the inside where there's an area where it doesn't matter that you have a solid line, you could just put a piece of paper and just tape it just like that. This is gonna be behind the door anyway, so it's not gonna matter.

Now I'm gonna take some primer, just follow the directions on the can, shake it up real well and make sure the temperature is correct and give it a light coat. You might give it a couple coats, depending on how thin it goes on. And just go past the mark. So start the can here and then stop and then start just like that. You don't want drips. And again, like I said, I'm going downwards.

Now, when the primer's dry, this area where you spray the primer directly is pretty smooth. And if you go up to the top part where the paint particles are a little bit smaller, it's really rough in this area. So we're gonna have to address that. And then also, if there's anywhere where you had a tape line, you're gonna feel that tape line. So we also wanna address that. What you could do is move your tape back a little bit.

Now, to fix both of these, I'm gonna take some 1500-grit wet sandpaper. And I like to use a sponge just to prevent getting finger lines in it, and then, just lightly smooth this out. Just a little bit, until it feels smooth. It feels pretty smooth. That's good. And then, with the paint line, you can do the same thing. Just so it fades out a little bit. This will just help disguise it a little. Just feel that line went away a little bit.

So, with your tape line right there, it's a good idea, even if you didn't wanna sand that down a little bit, just to pull the tape up and just move it a little bit over and that'll be all set. Then, when you go to paint, it'll cover that tape line. And then, if you had your masks up here, if you got some of the primer up here, you might wanna move those up a little bit as well, before you spray your color.

Since we're only doing the rockers in a small section of the rear quarter panel, we're using color-matching spray paint. It's gonna be a lot cheaper and a little bit easier to use than mixed paint.

Now, after you spray the paint color, it's a little bit dull. You wanna shine it up a little bit. So we're gonna spray some clear coat; pretty much the same exact method as spraying the color.

So, this came out pretty good. Everything's dry. It had a chance to sit over the weekend. And there's a couple areas that I messed up a little bit, I got a little bit of a drip there. I don't know if you can see it too well. That's okay, we're gonna try to fix that. And up here, it's not very smooth. That's from the little paint particles. So we're gonna fix that up also. Let's take all the paper off.

All right, before we go any further, we're gonna put everything else back together and put the doors on.

Before we put the rear door on, we're gonna have to put this trim piece on. Well, the original way to secure this trim piece was these clips. Now, the new panel doesn't come with the holes that line up with the clips, so you either have to drill new holes...it's not gonna be that easy, so line this up and find where it goes. And you could drill two holes and then try to carve it out in the middle. It's gonna take a lot of time. So what we're gonna do instead is find the ones that aren't there, and we're just gonna cut these off. And you can do this if you want, or if you wanna spend the time, drill the holes, cut those off. Same with this one. Just like that. Clean this up. And then, you can put some double-sided tape on here, and it'll secure just fine. And just line that up. Pop those in and then push that down. Perfect.

All right, so that turned out pretty good. So we have our new paint right here. We have our old paint up here, right in the middle, it's nice and rough. You can see a little bit of a line but it's not a harsh line, which is good. So we're going to take care of that. Now, one thing I didn't mention, when we were putting this panel on, was test fitting the door. If you were trying to get it to look exactly perfect and get this to line up, you probably wanted to put the door on, at that time, before you welded it on. But we didn't do that and it came out pretty good.

So, first thing I wanna do is just wash this area up. Get some water. Should probably use some soap and water and just clean everything. We don't have a hose in here, so do the best you can.

Now, to get this roughness out, I'm just gonna take some 1500-grit sandpaper, wet sandpaper, and a sponge and just gently gently sand that away. Constantly check it.

I got most of that texture out, so just to make it a little smoother, I'm gonna switch to 2000 grit. Just do the same thing.

So this is that area where that drip was. It's kind of hard to see on camera but there is a drip there. So what I'm gonna do is just take some 1000-grit wet sandpaper with a sanding block and just gently try to sand that out.

All right. So I got rid of the bump, so that looks pretty good. Luckily, I put a lot of clear coats on, I put probably three or four coats of clear on, which gave me a little bit of room to be able to do that. If you only put one or two coats on, you probably wouldn't be able to do that.

Now I'll go back with 2000 and just sand it down. So I masked off all the areas that I don't wanna hit with the buffer wheel and any of the trim. You don't wanna get any of this compound on the trim, whether it's the chrome or even any of the black trim. It leaves little marks and it's hard to get those marks out, so you're better off just covering it up.

All right, I'm gonna start out with a medium-cut, medium to heavy-cut compound. Just put a couple dabs on there. And if you think of this as almost like a paste with sand in it, then the heavier the cut, the bigger the sand is gonna be. The finer the cut, the smaller the sand is gonna be. So let's put this on here. And we're gonna try to bring some of that shine back right now. It's pretty dull because of us sanding.

All right. So that brought the shine back, so that looks pretty good. You almost can't see that drip at all. I can see it a little bit just because I know where it is. That's as far as I'm gonna go as far as bringing the shine back on this vehicle. If I wanted to, I could use a higher cut and shine it up even more, but then I'd have to buff the entire vehicle. And for the age of this vehicle, that's as much as I need to do. Now I can just put a little bit of wax on it, it should be good.

All right, now I'm gonna take some wax and use an applicator and just pretty much do what the instructions say to do on the wax itself. And this is gonna protect it and make it shine a little bit more.

All right, now I can take a microfiber cloth and wipe it off after it's sat for a while. So, if you look at it real close, if you compare the paint, you really can't tell where the old paint is and the new paint. It blends together real good.

Originally, there was a step here, or running board, and they were in really rough shape, so we're not gonna put those back on. But if you had those on your vehicle, you'd wanna put those on at this point.

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