2004 Chevy Silverado Rear Air Suspension Installation - Makin' It Lay Part 1
How To Lay Your '99-And-Later Silverado Down On 22s
From the October, 2005 issue of Sport Truck
By Kevin Whipps
Photography by Kevin Whipps
In the '90s, you could rock a set of 15-inch Boyds on your truck all day long and you were the coolest guy on the block. As time went on, wheels got bigger, tires gotsmaller, and trucks got lower-a lot lower. Laying frame is now the standard measure of a cool ride, and laying body is that much cooler. We get a lot of questions about how to do things here at Sport Truck, and one of the more popular ones is "How do I make my truck lay frame on X-inch wheels?" With this in mind, we decided to show you how to lay out one of the most popular trucks on the planet, the Chevrolet Silverado, on 22-inch rollers.
There are a few things to note before tearing into this article. Although the '99-'05 fullsize trucks are very similar, a few changes are made from year to year. In 2001, GM added a transmission crossmember to the frame that hangs down about 2 inches below the 'rails. If you don't do something about it, you won't ever lay the frame flat on the ground and won't be as low as the truck in this article. Don't worry, we tackled it on this truck, which happens to be an '04, so follow along and we'll show you how to eliminate that pesky obstruction beneath the tranny.
You also have a lot of options for how to get your truck off the ground once it has laid it on the frame. In this case, we chose an airbag suspension using high-quality components. As the old saying goes, you get what you pay for. That couldn't be truer than when purchasing airbag components. All of our fittings are DOT-approved, as well as most of the air tubing we used. Your setup may vary from what we installed, but remember not to skimp on the important items, such as the valves, the fittings, or the compressors. We used a few brand-new items in this install that made our lives a lot easier. For example, we installed a new bridge-notch kit from KP Components to provide clearance in the framerails directly above the axle. It's bent to match the kink in the factory frame, which made installing it a breeze. We also installed new Digital Stealth Valves from Slam Specialties. These valves have two different speed settings, which allow you to go fast up and down, or slow up and down, depending on your mood. That's amazingly convenient to those who don't want to smash their truck on the ground just to lay it out.
Follow along with Part 1 of this article as we do whatever it takes to lay down this '04 Chevy Silverado on some 22-inch Bonspeed rollers. Also, stay tuned next month as we wrap up the whole deal in Part 2. To find the parts seen in this article, don't forget to check out the source box.
1.Exhaust Before we could...
Before we could get the truck on the ground, we had to move some of the obstructions out of the way. First on the list was the exhaust Y pipe. As you can see, it hangs down really far on our truck.
2.Luke from Mighty Muffler,...
2.Luke from Mighty Muffler, in Phoenix, started by cutting the stock catalytic converter and crossover pipe off of the truck, resulting in two separate pieces.
3.Then, he twisted the catalytic...
3.Then, he twisted the catalytic converter over for more clearance and welded it back in place.
4.The crossover pipe was twisted,...
4.The crossover pipe was twisted, too, which lifted it above the frame in the process.
5.Just like that, the exhaust...
5.Just like that, the exhaust was now tucked under the frame.
6.One last thing, we had Luke...
6.One last thing, we had Luke add a turn-down to our exhaust, so it would exit in front of the axle.
X-MemberTo start, the transmission was supported by a jack and a piece of wood so as not to dent the tranny pan.
8.Using a 21mm socket and...
8.Using a 21mm socket and wrench, we were able to remove the four bolts that secured the crossmember to the frame.
9.There was also one bolt...
9.There was also one bolt that we had to remove, hidden way up inside of the crossmember.
10.There were a few wiring...
10.There were a few wiring harnesses attached to the crossmember with clips, so we removed them temporarily.
11.Once all the bolts were...
11.Once all the bolts were out, we removed the crossmember.
12.It's pretty easy to see...
12.It's pretty easy to see the huge difference between the two crossmembers. The KP Components part also comes with additional parts for reinforcement.
13.Bolting in the new KP crossmember...
13.Bolting in the new KP crossmember was simply the reverse of the tear-down and just as easy.
14.We finished the install...
14.We finished the install by cutting off the remaining brackets that were level with the frame and welding in the provided reinforcement plates.
15.Gas Tank X-Member The tanks...
X-Member The tanks on these trucks lay incredibly low, and besides that, they're plastic. Also, with the axle being so high, the driveshaft tends to hit the crossmember unless it's raised. We decided to raise the tank 1 inch, which keeps it under the floor but also above the frame. We started by marking the crossmember for reference.
16. Using some scrap steel...
16. Using some scrap steel to keep the crossmembers aligned, we cut out the two pieces to lift them.
Once it was lifted, we welded...
Once it was lifted, we welded it back into place.
17.Later on, when we were...
17.Later on, when we were putting the gas tank back in, we notched the cab for clearance.
18.Engine Bay The wheels won't...
The wheels won't be able to tuck into the fender wells with all that stuff in the way, so we're going to have to make some adjustments.
19.After pulling everything...
19.After pulling everything off, we used an air saw to cut out the wells.
20.With the wheels removed,...
20.With the wheels removed, we now had to deal with the battery and the computer. The computer mounts were moved forward to accommodate the wiring.
21.The battery tray fit just...
21.The battery tray fit just right when we opened up the mounting holes, removed the windshield washer fluid, and pushed it forward a little bit.
22.We made a mount for the...
22.We made a mount for the fuse box that uses the stock bolts. It wasn't very difficult to do and keeps it out of the way of the tires.
23.The coolant overflow tank...
23.The coolant overflow tank was mounted using the same hardware that held it on before. We just cut them out of the fenderwell and welded them into a location farther forward on the fender.
24.The intake had a custom...
24.The intake had a custom bracket built to hold the filter in place near the core support.
25.One last thing to note:...
25.One last thing to note: We had to remove the hood hinges because they were hitting the tires.
26.KP Components Install With...
26.KP Components Install
With the bed off and the truck on jackstands, we started by taking off the rear leaf springs.
27.Taking off the stock shackles...
27.Taking off the stock shackles is a ton of fun. We used a 4-inch Grinder to melt the heads off of the factory rivets, and then used an air chisel to knock the rivets through. In the areas that are more difficult to reach, we used a die grinder to cut an X through the head. Then, we used an air chisel to knock off the rivet.
28.The KP mounts bolt on where...
28.The KP mounts bolt on where the factory shackles used to reside and couldn't be easier to install.
29.The axle mounts provided...
29.The axle mounts provided with the kit bolt on just like the leaf springs. The passenger-side assembly (pictured) also has the brackets for the Panhard bar integrated into it.
30.The rear mounts bolt on...
30.The rear mounts bolt on the same way the front ones do, but we had to drill four additional holes in the frame.
31.Assembling the link bars...
31.Assembling the link bars was pretty simple. We made sure that all of the bars were the same length. Otherwise, we would have had alignment issues later on.
32.The forward link bars were...
32.The forward link bars were then bolted onto both the frame and the axle.
33.The rear bars were bolted...
33.The rear bars were bolted up the same way. For now, we're leaving the 'bags out of the system, since we still have some welding to do. And, we also have to install the front suspension and air delivery system. We'll tackle that next month, so stay tuned.
34.You don't have to do a...
34.You don't have to do a huge notch in this style truck to make it lay frame. What we did was use the KP Components four-piece bridge-notch kit and some 1-inch tubing to space it up off the frame.
35.The notch was then welded...
35.The notch was then welded into place on all sides.
36.To mount the Panhard bar,...
36.To mount the Panhard bar, we had to bolt in this mount to the frame. You can weld this plate in, if you so desire.
37.Time to mount the rear...
37.Time to mount the rear 'bags. The kit came with studs to mount the 'bags to the link bars, so we installed them into the bottom of the Slam Specialties airbags.
38.Next, we bolted the top...
38.Next, we bolted the top of the 'bag onto the mounts.
39.The shocks completed the...
39.The shocks completed the kit, and they held on with the provided Grade 8 bolts.
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