Why Your Super Duty Hops…And What You Can Do To Stop It
It happens off-road, at the track and even on the street. It’s front wheel-hop and it’s extremely common on ’05-‘16 Ford Super Duty trucks with four-wheel drive. Under big load, the factory coil spring, radius arm front suspension’s design fails to limit the axle’s rotation. In the diesel realm, where a significant amount of additional power is almost always in the mix, the problem is exacerbated further, with violent shutter and bouncing being common when drag racing or truck pulling. Throw a couple hundred extra horsepower, a leveling kit and a set of aggressive tires at a late-model Power Stroke, and you’re bound to experience front wheel-hop.
Fortunately, Ford’s same basic front suspension geometry has been around a while and there is no shortage of enthusiast-born solutions for this frequent problem. From stiffer shocks to dual shock arrangements and nylon straps to complete four-link conversions, there is a recipe for everyone—and for virtually any budget. To find out more about each option, keep reading. You don’t have to ditch your lift, your mud terrains or your power adders to keep your Ford’s front-end digging!
So why is it so easy to unsettle a coil sprung Ford’s front-end? It’s a combination of radius arms, the radius arm bushings and the Super Duty’s overall suspension geometry. Despite its two-point mounting arrangement on the axle itself, the single link radius arm system cannot fully control the axle’s rotation. Once the torque load being applied to the tires overcomes the factory suspension system’s capacity to keep the axle in place, the axle’s housing rotates the opposite direction the wheels are turning. When this happens, the suspension becomes unsettled and the pinion actually tries to climb up the ring gear.
Rancho 9000’s (It’s a Start)
This is by no means an end-all, be-all solution to wheel hop, but it can help. For years, Super Duty owners have flocked to the Rancho RS9000XL shock absorber, mostly for its adjustability. In total, nine positions are available, with the stiffest setting being preferred by most (especially truck pullers and drag racers). While adding the Ranchos helps limit hop on some trucks, for most it doesn’t, which brings us to the dual shock solution below.
Adding a Second Shock
On both high-powered street queens and trucks that hook to the sled, adding a second shock (per side) to the equation has been proven to quell front-end hop. Perhaps the biggest benefit is that it’s relatively cheap. The trick for many truck pullers has been to position the additional shock in front of the axle and at a 60-degree angle. Mounting it in this fashion provides more leverage and we’ve seen it successfully campaigned by countless truck pullers over the years.
One of the most substantial ways to eliminate front wheel-hop is to scrap the radius arms altogether and convert to a four-link. The ‘05+ front four-link system manufactured by RCD Performance is one of the most proven setups on the market. A complete bolt-on kit, it accommodates trucks that’ve been lowered up to 2-inches or Super Duty’s that’ve been treated to as much as 4-inches of lift, with very little (if any) after-install tweaking being necessary, should the customer want to fine-tune caster. The four-link works by loading the top link while pulling on the bottom link—thereby combatting the axle housing’s natural tendency to rotate the opposite way the wheels are turning under high stress.
Zero Hop = Quicker E.T.’s
With RCD Performance’s four-link system bolted underneath this ’08 F-250, the severe front-end bouncing it experienced with the factory radius arms disappeared. Instead, the front-end dug in during boosted, four-wheel drive launches at the drag strip, providing much better traction for getting out of the hole. In fact, with no other changes, the 6.4L-powered Ford started turning in 1.69-second 60-foots. With the factory radius arms—and all the lost traction and pedaling that came with the bouncing—it used to turn out 1.8 to 1.9-second 60’s. The added grip on the starting line equated to high 11.80’s in the quarter-mile (vs. 12.30’s before).
Flight Fabrications also offers a highly-refined four-link conversion kit for ’05-newer Super Duty owners. And like RCD Performance’s four-link system, it maintains positive caster throughout the suspension’s travel. So not only is the wheel-hop issue solved, but the negative caster, steering wander and twitchy steering associated with the factory suspension is done away with. Many cases of death wobble have been brought to a halt with this system, too. As a bonus, Flight’s four-link kits are completely TIG-welded and ship with Grade 8 mounting hardware.
Catapulted into the 8’s
Out in the real world, Flight Fabrications’ four-link system has been campaigned by former Ultimate Callout Challenge competitor, Sam Gabel. With traction never being an issue thanks to the four-link conversion (1.5-second 60-foots), his nitrous-huffing, 6.4L-propelled Super Duty has gone 8.99 at 154 mph in the quarter-mile—that’s third fastest among all Power Strokes. Sam’s Ford has also been 5.83 at 125 mph through the eighth-mile as well, so it’s pretty evident that his 5,000-pound ¾-ton has no problem maintaining traction during boosted, four-wheel drive launches.
One More Vote for Four-Link
Another four-link fan is Travis Trent, who sports one of Flight Fabrications’ systems on his Cummins-powered ’05 F-250. His high-powered, NT420S-equipped, short-bed creation has been high 9’s in the quarter thanks to instantaneous traction. Perhaps even more impressive is the 1.60-second 60-foots he’s also been able to cut with his suspension, tire and horsepower combination. In the world of motorsports, lost time (drag strip) and lost momentum (truck pulling) due to lost traction is devastating. Luckily, late model Super Duty’s running four-link systems such as this don’t have that problem.
Grabbing the Holeshot
Designed specifically to help dial in front-end weight transfer on ’05-’19 Super Duty’s, Flight Fabrications’ holeshot kit works wonders for drag racers and sled pullers alike. Its quick-adjust straps limit front wheel travel, stopping the chassis’ tendency to unload on the launch. The 2-inch wide webbing the limit straps are made of is rated for 10,000-pounds and the mounts simply bolt on to your existing shock location (and even come with hitch pins for easy removal when you’re not at the track).
Strap It Down (It’s Cheap & Easy)
When all else fails and you just want a temporary solution (such as at the local truck pull or test ‘n tune night at the drag strip), grab a pair of two to 3-inch wide rachet straps. Run each strap over the cross member and then back around the axle tube and get to tightening. Strapping the front-end down is a sled pulling trick that’s been used for decades. It’s cheap and it works, but again it’s a temporary solution. Most front-ends will drop roughly two inches when strapped down, with the bump stop nearly touching the axle.
Rocking an ’01 or newer Chevy or GMC HD? Your front suspension needs help, too! Find out what you need to bulletproof your IFS right here.