Top Shelf: Carli Suspension’s 4.5-inch Coilover Conversion Improves This Workhorse 2016 Ford F-350Posted in How To: Suspension Brakes on June 10, 2016
Sam Meyers, the owner of a logging company in Oregon, “uses and abuses” the Ford Super Dutys in his fleet. He loads them down with transfer fuel tanks in the beds, drops heavy trailers on the hitches, and fills the four-door 4x4s seats with crew. And when downtime comes around, he snaps a 43-foot toy-hauling gooseneck into the bed of “the boss’s truck,” an F-350 Lariat, and heads to the dunes or desert to unwind.
Spending just about every working day driving over twisty, paved mountain roads and rough, muddy gravel roads freshly cut to access the logging operations, Sam wanted to find a solution to smooth out his time behind the wheel of his ’16 Ford without compromising its factory towing or load ratings.
He also wanted more suspension travel and the best shocks he could find to make towing the heavy 43-foot toy hauler more comfortable on long road trips, along with enough lift to run taller tires for more ground clearance on those days when the ruts get deep, as they always do around logging sites.
Having tried more traditional lift kits in years past, Sam opted for a more radical approach to making the suspension on his brand-new F-350 Super Duty do everything he wanted: replace the factory front suspension with a Carli coilover conversion along with King 2 1/2-inch bypass shocks at all four corners like race trucks run.
His top-shelf approach to modifying the Super Duty suspension offers numerous benefits over the factory setup: it adds up to 4 1/2 inches of lift in the front and 2 1/2 inches in the rear, leveling the factory stance while the front coilover bypass system allows 10 inches of wheel travel in front and the rear bypass shocks a foot of travel.
Carli’s kit is said to give a smoother ride both on-road and off. Additionally, cornering handling is greatly improved with less body roll, and steering response is tighter with all the geometry staying within Ford factory specs. The bonus is the coilover conversion doesn’t affect the OEM towing or load ratings.
The only option needed was a driveshaft carrier-bearing drop kit ($35) to keep the pickup’s two-piece driveshaft assembly at the proper factory angle that his longbed truck required. Carli also suggests replacing the stock tires/wheels with E-rated 37s mounted on either 17x9s or 18x9s with 5 inches of backspacing and running the tire pressures at 45 psi in front and 40 psi out back for optimum results.
The Carli coilover conversion kit for ’11-’16 Ford F250/F350 4x4s retails for $5,060. That’s a chunk of change, but one look at the components and it’s easy to see the expense is justified by the quality of the CNC machine work, the welds and gusseting on the shock tower brackets, the quality heavy-duty adjustable track bar and sway bar drop brackets, and the time put into custom tuning the race-quality King 2 1/2-inch shocks for this specific application. Even the kit’s progressive-rate rear spring packs are high-end.
We watched the conversion from beginning to end. Casey Castle, lead suspension tech at Dunks Performance in Springfield, Oregon, handled the wrench turning, following very detailed and nicely illustrated instructions for installing each component of the kit.
Casey was impressed, as were we, by the quality of the engineering and precision of the fit. Every part bolted or matched up exactly as indicated. The new coilover tower brackets are even fabricated to bolt in the extra bypass shock should that be needed later on.
That same precision showed up on Dunks’ computerized John Bean V3400 alignment system. Alignment technician Richard McFarland found caster, camber, and toe to be at or very close to factory specs, so fine-tuning the alignment was easy. Carli even provides new 1.0-degree bushings in the kit to set caster.
Richard used the new bushings and adjusted this truck’s caster to 4.5 degrees (factory specs are 2.4-3.7), “To help it track better and easier to steer. We’ve learned over the years of doing suspension lifts and coilover conversions that adding one extra degree of caster really improves handling.”
We took a ride after the conversion and noticed how nice the truck drives, with quicker steering response, flatter cornering, and faster-reacting suspension. While the front suspension feels more pliant, the 6.7L F-350’s rear suspension still feels like it can easily handle 3,000 pounds in the bed or carry 14,000 pounds of gooseneck trailer. But now when it’s put to those work-type tasks, the new suspension will be considerably more controlled with more travel than it was before the Carli coilover conversion. That’s exactly what Sam wanted.
|Ride Height/Front (in):||41||44.75||3.75|
|Ride height/Rear (in):||43.5||46.5||3|
|Approach Angle (deg):||33||39||6|
|Departure Angle (deg):||29.5||32||2.5|
*Measurements with stock OEM tires/wheels and coilovers at the standard height
Carli’s Ford Super Duty 4x4 4.5-inch coilover conversion kit levels F-250/F-350s while clearing the way to run 37s. The kit greatly improves on- and off-road handling without compromising factory towing or load-carrying ratings.
Carli uses 1/4-inch cold-rolled steel to fabricate the coilover mounts that replace the Ford OEM front coil buckets. The rivets holding the factory buckets to the framerail are cut off, and then the Carli mounts bolted in their place using the same mounting holes. This makes it easy to return the truck to stock if needed.
The sleek radius arm drop brackets fit without any modifications and bolt right to the Super Duty frame. Carli’s “dimpled-died” design of the 1/4-inch steel brackets and crossmember keep weight down while maximizing strength.
Our ’16 F-350 is the FX4 version fit with Rancho shocks. The Carli conversion replaces the OEM shocks, coil springs, and tower buckets with custom race-type coilovers and fabricated towers.
Dunks Performance tech Casey Castle finds the easiest way to remove the big rivets that attach the OEM coil buckets to the frame is with a plasma cutter. The new tower mounts bolt into the factory rivet holes, and two new holes are drilled into the bottom of the frame for additional support.
The finished front conversion from coil to King 2 1/2-inch coilovers looks factory. Carli provides new braided brake lines and special bottom brackets to make the installation a relatively easy bolt-on job.
At the heart of the conversion are the custom-built King 2 1/2-inch front coilovers. They utilize shot-peened preset coils with a progressive variable rate for smooth transition from small bumps to big dips. Ten inches of wheel travel is almost double that of the OEM FX4 shocks.
An installation trick Casey uses to make the Carli drop-brackets align easily with the factory radius arms is to place a ratchet strap around the axle and tie rod as shown. Tightening up the ratchet rolls the back of the OEM radius arms up/down. The axletube is supported by a pair of tall jackstands.
Spring center bolts can be easily stripped when tightening with the addition of the progressive-rate Carli Add-A-Pack. Casey raises the jackstands under the axlehousing and uses a pair of 5-inch C-clamps to keep pressure on the spring pack as he tightens the spring center bolt.
The rear King 2.5-inch bypass shocks mount into the existing OEM shock brackets, making this a straight swap-out. Carli’s remote-reservoir shocks have custom valving specific to the Super Duty and considerably more travel than the OEM Ford FX4 shocks.
Casey thought the clearance between the driver-side framerail of our truck and the King shock was too close. He trimmed off a 1/2x2-inch triangular piece (held by tape for this photo) to eliminate any possibility of rubbing.
Our longbed Super Duty has a two-piece driveshaft that requires the center carrier bearing to be spaced downward to keep the driveline angle within factory specs. We used Carli’s optional ($35) spacer, which took Casey all of one minute to bolt in place
Richard McFarland rolled our lifted F-350 on Dunks’ John Bean V3400 alignment machine after the Carli kit was installed. The computerized laser-alignment system showed this truck to be very close to factory specs, which he quickly took care of with a couple minor adjustments.
Here’s an alignment tip: Dunks has found adjusting caster 1-2 degrees more than factory spec (2.4-3.7 degrees for the 2016 F-350) gives lifted 4x4s excellent highway manners. The Carli suspension kit comes with 1-degree caster/camber alignment bushings (left), which Richard installed to get the ideal setup.