The Ground Force leveling kit (#91200) drops the rear of the 2WD F150 approximately 2-in. or 1.5-in. for 4WD trucks) to level out the stance. Unlike other leveling kits they smartly include pinion shims to correct driveshaft angle and eliminate any driveline vibration.

With four months and a little over 4,000 miles the 2006 F150 is really growing on me. Besides a fluke no-start condition that resulted in a warranty PCM replacement the F150 platform, redesigned in 2004, has proved to be everything people have been raving about. The 4.6L 2V engine is torquey and while I haven't had a chance to tow with it, it has handled heavy bed loads just fine. This F150 is the base-model STX, which I selected primarily due to its low price tag, but also because of its monochromatic color (the XL and XLT's come with chrome bumpers.) The draw back to the STX model however is the lack of creature comforts such as power door locks and windows. We'll tackle those in the next issue, but in this article we're addressing an aesthetic nuance common to all '04-'06 F150's; the very noticeable stinkbug stance.

Ford designed the new F150 suspension with a hefty rake so the truck is higher by about 3" in the rear then in the front. This is obviously done to accommodate for heavy loads in the bed. However aside from contractors we suspect most F150 owners aren't loading up the bed to max capacity on a daily basis. If your mentality is anything like mine, I'd rather have a good looking and level stance on the days I'm not hauling then on the few days I am.

There are a couple of options for leveling out the new F-150. You can raise up the front with coil-spring spacers, or you can drop the rear down. It's all about personal preference, and I preferred to lower it. Since I don't plan on changing out the factory 17" wheels any time soon I figured anything that helps reduce the big fenderwell gaps would be good.

To lower the rear we used a leaf-spring shackle kit from Ground Force suspension. They have been modifying truck suspensions for 30-years and know how to alter the factory suspension without altering the stock driving characteristics. Unlike many shackle kits on the market for these trucks the Ground Force kit includes pinion wedges to correct the pinion angle, since it will change upon lowering.

The last thing any new truck owner wants is to tear into his rig without knowing how difficult the task will be or if there is the chance the truck will be out of commission for longer than expected. Rest assured the leveling kit can be installed in two hours flat, with basic metric hand tools, a floor jack and jack stands. We had no surprises and everything needed to finish the job is included in the kit. The truck looks great (see the before and after photos in the sidebar) and handles just like it did from the factory, if not a little better. Take a stance and level your new F150, it's worth it.

Working on a level surface we jack up the rear of the truck and support it with jack stands under the frame rails. The axle housing needs to also be supported with the jack.

Remove the lower shock mounting bolt and let the shock hang free and clear of the mounting bracket. Removing the wheels isn't necessary but makes it a little easier to gain access to the shock and leaf spring u-bolts.

Loosen the four leaf spring to u-bolt nuts using an 18mm wrench. To save a little time we only fully removed two of the nuts, the other two can be backed out just enough to let the spring bracket hang down. We sprayed the leaf spring u-bolts with WD40 to make for easier removal.

Use the jack to lower the axle housing assemble just enough to allow placement of the pinion angle shims. The thick end of the shim points towards the rear of the truck. Place the shim onto the leaf spring pins as shown.

Raise the axle up with the jack so that the leaf spring pin comes through the hole (arrow) in the spring mount as shown. Reinstall the u-bolts and nuts. Not sure of the factory torque spec we tightened each nut evenly in a back-forth sequence until we reached 80 lb.ft. Repeat the shim placement for the other leafspring.

With the pinion shims installed on each side we can move to the drop shackle installation. You can see here the difference in height compared to the stock shackle. We'll install one side completely and then do the other side.

Before removing any of the shackle bolts be sure your jack is supporting the axle housing assembly. Give it a couple of pumps to make sure the load is supported by the jack, otherwise the assemble could fall as you remove the shackle bolts.

Working on one side first, remove the lower and upper shackle mounting nuts. The lower bolt can then be pulled out.

You'll need to jack the axle assembly up high enough so that the top bolt can be removed over the frame rail as shown.

With both bolts removed the stock leaf spring shackle can be removed. We'll reuse the factory bolts but ditch the shackle.

A comparison of the stock and Ground Force shackles reveals how the drop is achieved. By raising the mounting point of the rear eye on the leaf spring we effectively bring the body down.

Install the supplied polyurethane bushings and sleeve into the new shackle. Use grease to prevent squeaking.

Installing the new shackle is in reversal of removal. Start by hanging the shackle over the rear eye of the leaf spring and installing the upper bolt. Note the open side of the shackle faces towards the front of the vehicle, this is opposite of how the stock shackle appears.

Using the jack lower the axle housing assembly until the shackle aligns with the bolt holes in the frame bracket. Then install the lower bolt and nut. Tighten up the lower and upper nuts.

Here is how the Ground Force shackle looks when installed. Repeat on the other side.

The pinch welded rail under the bed and directly over the shackles may interfere with the spring movement. Use a pair of channel locks to fold it over and flush with the underside bed panel.

In This Article:
We eliminate the stink bug stance of the new F150 truck with the help of some Ground Force 2" lowering shackles. Unlike other lowering kits Ground Force has designed their kit with pinion angle correction to eliminate any potential driveline vibrations.

Also See:

F150 Power Trip

Before: Here is the 2006 F150 in factory stance. On a level surface the truck exhibits a very noticeable rake due to the rear end being 2" higher than the front. We measured 37.5" from the ground to the apex of the rear fender well in stock form.

After: The shackle kit brought the rear end down exactly 2". The truck has a very slight 1/2" rake, but the improvement is very noticable.


Ground Force
714 Braddock View Drive
Mt. Braddock, PA 15465
(724) 430-2068


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