If you're looking at an 08 silverado 4 6 drop kit, you probably already know it's one of the best ways to get that aggressive, leveled-out stance without turning your truck into a frame-dragger. This specific drop—four inches in the front and six inches in the rear—is basically the "gold standard" for the GMT900 platform. It gets rid of that massive factory wheel gap and levels the rake so the truck looks like it actually belongs on the street rather than a construction site.
But before you start tearing apart your suspension, there's a lot to think about regarding how you're going to get there. It isn't just about making the truck lower; it's about making sure it still drives like a truck and doesn't bounce you out of your seat every time you hit a manhole cover.
Why the 4/6 Drop is the Sweet Spot
Most guys start with a 2/4 drop, but it usually doesn't take long before they realize it's just not enough. You'll look at the truck a week later and think, "I could go lower." That's where the 4/6 setup comes in. It's low enough to look custom and sleek, but high enough that you can still daily drive it if you're careful with driveways and speed bumps.
On an '08 Silverado, a 6-inch rear drop actually levels the truck out because the factory rear end sits so much higher than the front. If you only did a 4-inch drop in the back, you'd still have a bit of a "stinkbug" look. Going 6 inches in the rear puts the body lines parallel to the ground, which is exactly the look most of us are chasing.
What's Actually Inside the Kit?
When you buy an 08 silverado 4 6 drop kit, you aren't just getting a box of random bolts. Usually, the front and back are handled completely differently.
The Front End (4-Inch Drop)
For the front, most reputable kits use a combination of lowering spindles and adjustable struts or lowering springs. I'm a big fan of using 2-inch drop spindles. Why? Because they keep your factory suspension geometry almost perfect. If you try to get all four inches just from springs, your control arms are going to be at a weird angle, and your ride quality will tank. Using a 2-inch spindle plus a 2-inch lowering spring or an adjustable strut is the way to go. It keeps the ride smooth and makes getting an alignment way easier.
The Rear End (6-Inch Drop)
The back is a different animal. To get six inches of drop, you're almost certainly looking at a "flip kit." This basically moves your rear axle from underneath the leaf springs to on top of them. That move alone usually gives you about 6 or 7 inches of drop. Most kits include adjustable shackles too, just in case you need to fine-tune the height to make sure it's perfectly level.
The Reality of the C-Notch
Here is the part where some people get nervous. If you're doing a 6-inch drop in the rear of an '08 Silverado, you have to install a C-notch. There's just no way around it. Without a C-notch, your axle is going to be sitting maybe an inch away from the frame. Every time you hit a tiny bump, the axle will slam into the frame rail. It sounds like a gunshot and feels like the truck is breaking in half.
A C-notch involves cutting a semi-circle out of your frame right above the axle and bolting (or welding) in a reinforcement plate. It sounds scary to cut your frame, but these kits are designed to be stronger than the factory rail once they're installed. It's the only way to get your upward travel back so the truck can actually soak up bumps.
Shocks Make or Break the Ride
Don't even think about using your factory shocks with an 08 silverado 4 6 drop kit. They're way too long. If you try to use them, they'll be fully compressed before you even get out of the driveway. You need "drop shocks" specifically valved for a lowered stance.
Nitrogen-charged shocks are a popular choice because they react faster and keep the truck from feeling "floaty." If the truck feels like a boat after you drop it, it's almost always because the shocks are either cheap or the wrong length. Spending an extra hundred bucks on decent shocks will save your back and your sanity during long drives.
Wheel and Tire Fitment
Once you've got the truck sitting low, your stock tires might look a little chunky, or they might even rub. Most guys running a 4/6 drop on an '08 Silverado tend to go with a 20-inch or 22-inch wheel.
If you're staying with 20s, a 275/45R20 tire is a pretty safe bet. It's got enough sidewall to protect the rim but it's thin enough to clear the fenders. If you go with 22s, you'll probably want something like a 285/35R22. Just remember, the lower you go and the bigger the wheel, the more you have to worry about the offset. If your wheels stick out too far, they're going to catch the fender lip every time you turn or hit a dip.
Installation Tips for the DIY Crowd
If you're doing this in your driveway, give yourself a full weekend. It's not a two-hour job. The front is pretty straightforward—just unbolting ball joints and swapping parts. But the rear flip kit involves dropping the entire rear axle, which can be a literal heavy lift.
- PB Blaster is your friend: These trucks are over 15 years old now. Bolts are going to be rusty. Spray everything down a day before you start.
- Check your brake lines: When you move the axle on top of the springs, make sure your brake lines aren't being stretched or pinched. You might need to relocate the mounting brackets.
- Alignment is non-negotiable: As soon as you finish, drive (slowly) to an alignment shop. Your toe-in will be all messed up, and you'll eat through a set of front tires in a month if you don't get it fixed.
How Does It Drive?
I get asked this a lot: "Will it ride like a Cadillac?" Honestly, no. You're taking away a lot of suspension travel. But, if you do it right with spindles and a good C-notch, it shouldn't ride like a lumber wagon either.
It'll feel firmer. You'll feel the road more, and the truck will feel much more planted in the corners. The center of gravity is lower, so that "top-heavy" feeling of a truck mostly disappears. It handles more like a heavy sedan than a high-clearance pickup. For most people, that's a huge plus.
Final Thoughts on the 4/6 Drop
Choosing an 08 silverado 4 6 drop kit is a big commitment, but it's one of the most rewarding mods you can do. It completely changes the identity of the truck. It goes from being a generic work vehicle to a custom street machine that turns heads at every stoplight.
Just don't cut corners. Buy a kit that includes the C-notch, get some decent drop shocks, and make sure your tire size is dialed in. If you take the time to do the install correctly and don't skip the alignment, you'll have a truck that looks killer and still works for you every single day. It's all about the balance between form and function, and for the '08 Silverado, 4/6 is where that balance lives.