How many times have you heard that installing a leveling kit into your 1999-2019 Duramax will ruin your ride quality? We get countless phone calls from people who just pulled their brand-new Duramax off the lot and really want to give it a bit more aggressive of a look but have heard from their buddy that it’s going to wreck the nice ride of that new Chevy.
Likely, you’ve heard this too, so we’ve developed a few tips to think about before you decide to keep it stock, lift, or level your Duramax. First, we have to understand how your suspension reacts to a lift or leveling kit.
How the torsion bar system works
The GM IFS (Independent Front Suspension) system on the GM truck uses an upper and lower control arm on each side to hold the steering knuckle and provide adjustment for the wheel alignment.
The lower control arm is connected to a torsion bar which runs toward the rear of the truck and works like a spring. The Torsion bar is made of spring steel, this allows it to twist, this twisting provides the rebound in your suspension.
The rear of the torsion bar has a key attached to it and is anchored to a cross member located directly behind the transmission. Leveling kits for these trucks will include a torsion key that allows you to twist the torsion bar harder than the stock key. This forces the lower control arm down, which in turn raises the height of the front of the truck.
What’s the downside?
Installing a leveling kit on your Duramax isn’t going to immediately ruin your ride quality. Typically, it’s improper installation of a leveling kit that ruins your ride.
What can happen is if you try and get the full 2” (or even more) out of your leveling key, you can force the upper control arms onto such a downhill angle that they will bottom out on the frame stop. By doing this, every time you hit a bump, that upper control arm is going to drop down and can hit the frame stop, giving you a harsh “clunk” in your front end. Not only will you get the infamous clunk, but you’ll also be forcing that upper control arm down and forcing the upper ball joint at a harsh angle causing premature wear and damage by allowing it to move outside its normal parameters.
How we fix this.
There’s a reason we only recommend Kryptonite Suspension when it comes to the front-end on your Silverado or Sierra. Kryptonite has developed a control arm that will allow you to level your truck without running into these issues. Typically, the UCA’s (Upper Control Arms) are serviced as a unit, which means you can buy them with the ball joint already pressed in and replace the whole unit.
Alternatively, press in ball-joints can be purchased separately, however, unless you have access to a heavy duty press, you’ll have a tough time removing the ball joint from the control arm.
The Kryptonite UCA’s are designed differently, they are designed to curve around the frame-stop to allow the control arm to sit at the stock angle while maintaining the proper ball joint angle with either a leveling kit or even at stock height.
They do this by providing an upper ball joint that is bolted to the control arm rather than pressed in, which allows the installer to place the ball joint on the upper side of the control arm for stock applications or on the bottom for lifted applications. This allows for about ½” of adjustment either way on the ball joint.
Should you level your truck?
If you are looking for just a bit more height, you can easily squeeze 1.5” to 2” out of a leveling kit and without compromising your ride or running into issues. However, if you want to get as much as you can without springing for a complete lift kit, then we highly recommend replacing the upper control arms to keep your steering geometry in spec and avoid that clunk up front.
