Dump Truck Restoration, Improvements, & Spreading Stone in 2 Tracks. 1988 GMC C7000

Hey there, welcome back to FarmCraft. I'm continuing work on this 1988 GMC C7000 dump truck that I bought. In the first video, I did some repairs to it, delivered my first load of stone, popped a wheelie. If you haven't seen that, I'll leave a link in the description. We're continuing with some repairs in this video. A lot of different things going on here, so let's get to it. So this power steering reservoir leaks. I went to Napa and priced a new one. $125. Well I can tell you there is zero chance that I'm spending $125 for that. Let's see what we can do. You can see someone's obviously tried to fix it before. I've got this cleaned up, degreased it. I used brake cleaner on the inside, I want to get all that oil out of there. I've got a rubber stopper on this opening here, and I put a tiny little rubber stopper in the vent for the lid. It's still going to leak some, but what I'm getting at is I want to try to identify where in here that it's leaking. So let's put some soapy water on it. With a little compressed air, we ought to be able to... Oh yeah, that's pretty obvious. But I'm just using an acetylene torch and a brazing rod. I do not see any bubbles. Well that was a quick $125 tax-free earned. $125 for a reservoir. And don't get me wrong, I'm not busting Napa. I'm sure they're not making much on it. I guess it's just a specialty item that they don't sell a lot of and they're expensive. The air pressure isn't staying at the right level. So I'm taking this. This is the governor. This is what regulates the air compressor. What it was doing is sometimes the compressor would pump up to 70 psi and then stop. Other times it would be 90, other times it would be 120, and I even saw it 150 once. It's like something in here is stuck. I think there's like a little shuttle inside this that is operating some ports and loading or unloading the compressor. And see what we find behind here. Oh, I heard it. This one avoided the black hole. It's so simple. It's just a spring. Maybe it's just worn out. So I have a feeling I'm just going to need to get a new one, but I figured I would try. I replaced these o-rings. They definitely seem to have a better seal there now. Let's see if we can't put this thing back together and we'll give it a quick test. So the answer is it made no difference whatsoever. So I went to Napa and they had one of these for $19. I usually try to diagnose more and not just throw parts at things. But for $19, you know, I'd pay someone $19 to tell me if it was the governor or not. So I might as well buy it, put it on and see if that fixes it. If it doesn't, that's fine. I paid $19 for some good information. All right, new governor installed. Let's see if that makes any difference. All right, I figured out what's going on with my air problems. Let me explain a couple of things here. Big trucks like this have compressed air. They use it for two main reasons, suspension or air springs, and they use it for the brakes. This is an air spring. It's basically a big rubber bag. When you fill that full of 120 PSI air, pounds per square inch, that's a lot of pounds that that can support. This is a drop axle. The way this works, there's two sets of bags that are inflated depending on if it's up or down. When it's in the down position, these inflate. These push the axle down against the road. You actually have an adjustment in the cab. These are the controls. That is up and that is to put the axle down. This adjusts the down pressure and this shows you how much down pressure you have. Because it is possible to push too hard with one axle if you're not loaded that heavy, you'll actually lift up your drive axle. There are two more bags. They're hidden behind here. You can't really see them. I'm touching it now. This is a fixed plate bolted to the frame. This you can see has a pivot there so the axle can pivot on this point. And behind this, there's another plate coming up like that and the bag is in between. So when that bag inflates, it pushes like that and causes the whole axle to lift. That's the lift mechanism for the drop axle. So the controls, what it's doing is it's just toggling between, am I going to put the air here or am I going to put the air there? If it's in the up position, it puts the air here. If it's in the down position, it puts the air there. So what does this have to do with my air problem? You know, sometimes I'm at 70 psi, sometimes I'm at 90. It turns out both of these lift bags have big holes in them and the air compressor is just leaking like crazy when it's trying to lift this axle. And it can only get to 70 psi before it's producing all the air that it can and it just can't get any higher. What I didn't realize but has finally clicked with me is that at times I was engaging the drop axle when I was hauling some stone, when I blew out one of the back tires. Once I put the drop axle down, I'm no longer sending air to these leaking bags. I'm sending it to these bags that are good. Suddenly my air pressure is good. So I thought the regulator was off. No, the problem is these bags. Here you can see this in action. Right now I've got the drop axle set to lift and you can hear that air leak. I'm just turning it to down now and you can see the down pressure bag inflating and the air leak is gone. And now I'm flipping it back to up and the air leak is back. So that's my problem. My air compressor is fine. My governor is fine. I just have to take these leaky air bags that are trying to lift this axle out of the equation. This is a work light that Olight just recently produced. I like it. It's got a magnetic base, has a clip so you can like hang it on things. It pivots and it has both like a floodlight and also a flashlight. Pretty cool. There you can see the bag. After fighting with these bolts, I do believe this bag is ready to come out. Yep. We birthed it. I'm looking at this for the first time with you. It's interesting. I actually don't see an obvious hole. Let's see if I can get this one out. Yeah, it doesn't look so good. GABBAGE! One side actually doesn't leak. Using an air gun. And that doesn't leak at all. This side has the tear right there. And when I first checked it, it didn't seem to be leaking that bad but it depends on what position it's in. That can leak a whole lot of air pretty quickly. So that was my problem. Right there. Now I priced these. It's $175 plus shipping for a replacement. I think what I'm going to do, I'm going to put this one back in. Maybe once I fix the leak and the air pressure is appropriate, maybe it will be able to lift it on its own. If not, I'll still have the option of putting a new one in the other side. So let me shove this thing back in there. Alright, I just started it and ran it until the compressor cut out. And you can see just over 120. Right like it should. And blessed silence. No leaks that I can hear. So that's awesome. Alright, so I got a new inflation bag for the drop axle. I found one on eBay that had pretty decent reviews for $90 shipped. And this is where the bag goes. You can get a look inside. On the left there is the plate that it pushes against to lift the axle up. And then this side is the fixed side that it bolts to, to the frame. Let's see if I can get this thing in here and get these bolt holes lined up. So this is the tricky part. You have to take a bolt on an extension and get it through two holes to get it into this position. And then you line the bag up, pretty much totally by feel. I cannot see the bolt hole on the bag while I'm doing this. You just cannot see what you're doing. Might have gotten one. Well, it's different. Yeah? Got one of them in there. Ooh, I felt it catch right away. Because the first one's lining it up. Did it go in? Yeah. Hell yeah. That was way easier than I was expecting. Sweet. So I can push the air fitting through and screw this on just temporarily, but that's going to allow me to control that much easier to line up those other bolts. I bet you these are going to go. I can find the hole. It's always a problem when you can't find the hole. And that one just went right in. That is awesome. It's rare things go better than expected. I'll take it. So once I get this airline hooked up, I'll bring you back. This view, you should be able to see how this drop axle lifts. This is going to inflate. It's going to generate force in both directions. This is fixed to the frame. This is on a plate that's attached at this pivot and will cause this to come up. So let me go start the truck. I'm going to leave you there. Let me know if you see anything. Did you see anything good? Oh, wow. Yeah, that's hard. And the other side, too. And it looked like it did most of the lifting by 90 PSI. I kept going for a little while just to see. No leaks. All right. Drop axle fixed. Now I'm going to do these brakes because these brakes are sticking. This is actually the parking brake. And looking at it, the air brake canisters that are on this side are ancient. So I'm probably going to have to change the canister, too. Notice something here. This is a hub with how many bolts is that? Twelve bolts. And that one has six. This is actually the axle that came with the truck from GMC. That axle was added on by the company that turned it into a dump truck. So the way these work, GMC builds the truck, the engine, the rear axle, and the frame. And then, you know, you could make it into a lift truck or a crane truck or a dump truck or whatever. And the aftermarket company does that. And so this is not a GMC axle. So it's different. And so I'm going to have to see what I'm going to get into with that one. You guys have already seen all this on the other axle. So we'll do a quick breeze through. I'll just bring you for the interesting parts. Did I mention I had another blowout? Yep. The whole axle comes out of there. So this is a three and a half inch nut on this hub. And I don't have a socket for that. You really can't do without it. So I went in to NAPA. They didn't have it in stock. But it's on order. In the meantime, I'm going to work on this brake can. This is a really old one. This is one that has the parking brake, which there's a big spring in here that applies the brakes. And you need air pressure to release the spring. That way, the truck's safer. You need air pressure in order to apply the brakes. But if you lose air pressure, these brakes are going to apply themselves and stop the truck. And there's one of these on either side in the rear. The spring in here is so big and powerful that taking this bolt off and releasing this clamp is actually hazardous to your life. Guys get hit in the head with the spring when it pops and get killed. So they don't make them like this anymore and haven't for decades. This side is not clamped. This side of the brake can is crimped. So there's no way to undo it. This side, you can actually take that off and replace the diaphragm in there if you want to. Now of course, this thing is so old, I'm just going to take this thing off and replace it. This side has a more modern version. This one right there has a clamp on it. But this one there does not. That one is crimped so that you can't take that clamp off. There we go. So I'm going to take these air lines off. Now I take these off and I can take the canister off. That wasn't too bad. A little double wrench action. So there you go. I can move this one by hand pretty easily actually. So it was definitely the brake can that was the problem. So let's talk about brakes on a big truck. Did I just hear your eyes glass over? That's weird. No, this is way more interesting than you might think. If you've never driven a big truck or never really thought about this, you don't realize how important this becomes. When you weigh 46,000 pounds and you're going down the road, it's pretty intimidating. You need to know that you have a braking system that's going to work. You need to use the engine to help you brake. You just have too much mass and too much required to stop the vehicle. So what they do is they compress air and use that to apply the brakes. Originally that's all they did. And they made an air canister much like this one. This is a service brakes only. These are what are on the front axles. And they're also on my drop axles. All this does is when air is applied through this hose, it pushes the rod and the rod then applies the brakes. If you lose air pressure with this system, you will not have brakes. There was a time when trucks were made this way. The brakes worked, but occasionally something would go wrong. You'd lose air pressure and then the trucks couldn't stop. And of course, I'm sure many people were killed and they said, we got to do something. So think about it. What's a good engineering solution for that to make sure that you can always have brakes? Well, the solution they came up with is the spring brake. So this canister contains a spring brake and you're really not supposed to take these apart because it's dangerous. So of course I'm going to take it apart. For the record, I agree. This is a dangerous thing to do. I took safety measures, but I would not recommend anyone do this. Let me go through it as best I can. Hopefully I can explain this without it being too confusing. This is the service brake side. This side is essentially equivalent to one of the smaller canisters. And what you have here, this is your air inlet. You have a diaphragm, so that's going to be airtight. And then you've got a metal plate. And this is the rod that the clevis was on that applies the brakes. There is a spring here that defaults this side of the canister to off. So that spring, when you put this together, you know, assume that spring is in there and I put this on, it is going to try to retract the rod. When you put air behind the diaphragm, it's going to push the rod out. Make sense? Okay. So that is a service brake. They default to off and they're only going to apply the brakes if you put air pressure behind the diaphragm. The difference starts with this. This is just a rod here with a plate. And it has the ability to push on the diaphragm and push on the rod through the diaphragm without air pressure back here. So this can transmit what's going on in the other part of the canister, regardless of what the air pressure is doing in the service part. Now let's go to the parking brake. So there's a diaphragm right there. And there's another plate like that. And then there's this beast of a spring. This thing, I can't even begin to compress. I mean it, I can move it a tiny bit, but it's, it's a joke. It fits on that plate like that. And this was compressed that much. That's a lot of potential energy. I can tell you when it popped, it wasn't that bad. My safety rig was more than adequate to it, but yeah, you certainly would not want to get hit in the head with that. How much tension is on that spring? I can kind of estimate it because this, I figured it, it's 23 and a half square inches and you have to get to about 60 PSI before my parking brakes release. So you have to fill, there's the air inlet, you have to fill this with enough air pressure to push that spring back. That means about 1400 pounds of pressure needs to be pushing back against the spring and allow the brakes to release. And then at that point, you're using it, you're just using this side of the chamber when you're driving. This is a regular service canister. And when you put air pressure in here, it applies the brakes. When you allow the air pressure to leave, the brakes come off. So yeah, that was pretty cool. That's quite a spring. That's good steel. Maybe I could blacksmith something out of that. That'd be kind of cool to cut that up and make a knife out of it. Air brake knife. The other cool thing about air is that it's very easy to store a large amount of potential energy in a tank. Trucks have several reservoirs and they're often divided with check valves. So there's a front brake reservoir and a rear brake reservoir. If you're going down the road and say your rear brake reservoir rusts out or a hose blows and it loses its air pressure, the front reservoir is not going to lose its air pressure and it will continue to function. You've got a gauge on your dash which shows both the front and rear. Even if you're going down the road and the engine stalls, you have plenty of air pressure in your reservoir. You're going to be able to apply the brakes normally. I think most trucks can apply the brakes 10 full cycles without any additional air input from the engine. And then you also have a low pressure air alarm. So you're going to know well before you're out of air that something's wrong and you need to stop the vehicle. So the new brake cans come with a very long rod to be set up for different trucks. I just need to cut this off the same way it was. And rather than fighting with that old clevis, I actually got a new clevis too. This has pins that don't require a cotter pin. There's a little catch there that's spring loaded. First I want to change over my fittings. Oh, different size. Yeah, so that one fits. See if I have an adapter. I don't have the adapter, so as usual I don't feel like waiting. So I'm just going to make one. This is a piece of scrap brass left over from one of my many brass pours. I am going to get back to metal casting at some point. I would have liked to have gone ahead and put the threads on the inside too, but these are tapered. These are pipe threads. So they have to come from this direction. That's not the prettiest thing in the world, but at least I can put a wrench on it and I'll be able to take it out if I need to. Using a little Teflon tape. Alright, it's the next day, and there's the socket that I couldn't do without. Wow. Good old leverage. Man. Great, bearing looks good. I was worried about this being the axle that's always down. I was thinking these might not be in as good a shape. I dedicated these pants to this dump truck. Believe it or not, they are pretty much just out of the washer. That is a permanent look. There you go. Alright, so I got new pads for this, and the new pads came with all new hardware. Included in this bag of hardware are two of these. These are that part right there that is pressed into there with this sleeve around it. And getting them out can be a pain, but I should be able to do it with an air hammer. The other option would be something like a ball joint press, but I don't have one. I tried a propane torch with no effect, and a good sized hammer, which didn't do much either. I typically start out with propane because it's cheaper, it's more portable, it's just much easier to do. But propane doesn't burn nearly as hot as acetylene. This is a far superior torch if you really need to heat something. There you go. Alright, next. Sleeve goes in first. And then that guy will go right in. A little easier going in than coming out. How many of you guys just had a Johnson joke go through your head? You know it's funny, drum brakes on like a passenger truck or a car were always so complicated and such a pain, but these are really very simple. These are just basically a place to hook the big spring. There it goes. And then these guys, just click the corners of those springs hook in these holes right there. It's just a keeper to hold those in place. There. These will be opposed to each other so the big spring can go ahead and hook. You'll see that these just hook on the studs that we just replaced. And then you're ready to put it on. Once you put it on, you run these two springs between these two holes on either side. And that's it. So I like to put a clean pair of gloves on before I handle the shoes. That way I don't have to worry about getting grease on them. Here we've got them hooked together just like we had them. Top one's on. Spring that was on there. That's all there is to it. Doing the same thing on the other side. Took a grinder with a wire wheel and I cleaned this drum out. I mean you can see it's a little pitted. You know there's definitely some spots on it. But the thing is super thick. I don't see it breaking. I couldn't imagine that it's breaking is not going to be super consistent. Basically what I'm getting at, for some of you truckers out there that work on these kind of things a lot, is this like a safety issue or is this going to be fine for a farm truck? Replacing all the drums on this thing would probably cost me over $1,500. I'd really like to not, but I don't want unsafe breaks. So leave a comment. Let me know what you guys think. Cleaned the bearing up. I'm just going to drizzle some gear oil on it. That's the same thing that's in the rear axle. This axle is different than the other axle because it's the drive axle. It has a whole reservoir of gear oil in it that lubricates these bearings. So I don't have to worry about the whole grease packing thing for this one. Several people have commented that the bearings that I packed with grease were supposed to be lubricated with gear oil through the opening in the hub. I wasn't aware of that, but I've also researched that people have differing opinions on using grease versus oil in these axles. For a truck that sits for extended periods, grease may be better. Since I did not replace the seals, I don't think the gear oil would stay in there. So I'm happy that I greased them. I looked up the spec. Surprisingly, I only have to torque this thing to 50 foot pounds. You want to spin the wheel as you're doing it so that it seats well. And then you back it off a quarter turn. And there you have it. Reach in with a punch and bend the tab. This actually doesn't take a gasket. It takes sealant. You can see there was sealant on it before. So I'll get that cleaned up and we can put the axle back in. It says to put down a little bead, but it just won't squeeze out of the tube to allow that. So it's going to be ugly. Yeah, it really bugs me that I don't have the last two nuts. And I thought, oh, that's fine. I'll just take them off the other side. The threads are different over there. Apparently that axle was replaced at some point and the studs, they're not the same pitch. I actually found a couple totally random. You know, they're not the right nut, but they at least go on. So I can put those on and torque them down just to get the sealant. I think that nut's a perfect match. What are you talking about? Don't worry. It's just temporary. A wise man once taught me that it's only temporary unless it works. All right. So now I need to adjust the brakes. With a parking brake, right now, because there's no air pressure, the brakes are applied. So I have to start the truck, let it build up pressure. This rod will retract. And then once it retracts, I can adjust this to the proper position. All right. So this should spin. And it does. Nice. I have the wheels chopped. What you want is after an inch of travel, the brakes should be applying. So they should be hitting there and they're not. So I need to tighten them up. Yeah, that's actually pretty good. So basically once this rod gets to this point, now that wheel is hitting and doesn't want to spin anymore. Right there. But there, it'll spin freely. So that's good. Ha! Nice. Did I get that on camera? How about a little water out of the bed, dump it on your back when you let the jack down? You know, because why not? Anybody wants some rusty dump bed water dumped down your back? I highly recommend it. Check this out. You don't see that every day. Finally getting around to changing these fuel filters. Now I pre-fill these because obviously you'd have to bleed an awful lot of air. So that is what came out of that filter and it looks really good so I'm happy to see that. Now that's the primary filter. That's the first one out of the tank. So I would expect this one to be worse. But it still doesn't look too bad. So these are my drop axle controls which I would gladly mount to this plate here. The problem is, there's nothing to keep this, which is how you adjust the down pressure, in that hole. There's threads on this thing. Now it almost seems like it would be a nut like you have on an electrical conduit connector. But of course, those don't fit either. I even looked online for one, could not find one. Found one of these. It does not come with the nut. So I'm going to make one. So I found this piece of aluminum that I'm surprised I kept because it looks like garbage. This was the pour spout in a sand cast mold. But this is actually the right dimensions. Nice. Yeah, I gave that a nice texture that's going to make it real easy to tighten that down by hand. That is perfect. Remember that little wheelie I did? Yeah, me too. I have a solution. You guys confused yet? Here's my GoPro mounted to one of these magnetic bases. So here's the cool part. On a GoPro, I can connect it to my phone and enable preview. So there you can see, I have a view now of the bed and that's real time. So now when I'm dumping, I can set this up and I can keep my eye on that and know, okay, I don't need to put the dump up anymore. That at least will help me as I'm figuring things out. So I'm about ready to start spreading stone. My driveway though is a well established drive. If you're putting in a new road, you want to spread full width, obviously. But on a drive that's established like this, you end up getting two low spots where you drive and a high spot in the center. You don't want to spread stone across the whole thing. So you need to spread it in two tracks. Now there's various ways to do this. What I'm about to show you, in my opinion, is the best way. Before Evolution sent this to me, I honestly didn't know a saw like this existed. The big whoop you say? Jobsite table saw. That's nothing new. It's a little different than the Jobsite table saws I've used in the past. Obviously that's not built to the standard to be able to tow a trailer. That's not what it's for. How much weight is this thing actually going to be taking? It's going to be getting hit with stone that's fallen like this far and then deflecting. So I don't think it's going to be holding more than a couple hundred pounds at most, if that. This piece here is not super thick. It probably used to be an eighth of an inch, but it's rusted quite a bit. And that's all I really had to weld to. So I built this thing and I put a foot on it there. I didn't weld it to this, because that's just the skin of the bed up above. It's just pushing up there, so the more weight that goes down on the diverter, the more this is going to want to go up. It's going to push into the bed and, well, the bed's full of stone. That's going to prevent it from deflecting at all. It's plenty strong for what it needs to do. I think we need to try this thing out. I got my GoPro set up so that I can see in the bed while I'm dumping and get a feel on how fast it's coming out. I cannot record and do that at the same time, unfortunately. Well, not perfect, but no wheelies. The diverter plate worked. And there she is. Tomorrow, 15 tons.