Close-up view of the FOX 3.0 Internal Bypass shock that adapts to terrain in real-time, optimizing its 13-in (330 mm) front suspension travel and 13.9-in (353 mm) rear suspension travel. (Ford Performance)

Ford gives 2019 Raptor smarter shocks, new trail control electronics

Electronically controlled shocks and a new Trail Control system that automatically adjusts power and braking at each wheel lead the 2019 Ford F-150 Raptor’s suspension upgrades.

“We’ve evolved the F-150 Raptor’s off-road performance with a new Trail Control system and the first-ever automotive application of a position-sensitive active damper,” Chris Paiva, Raptor’s vehicle dynamics engineer, said in an Automotive Engineering interview during the truck's recent unveiling.

Raptor’s electronically controlled Fox 3.0 Internal Bypass shocks with Live Valve technology are a derivative of the type of shocks used in side-by-side ATV applications. Ford Performance engineers and Fox technical specialists evolved the shock absorber system for its full-size pickup truck debut.

The shock absorbers have three settings (normal, sport, off-road) integrated into the terrain management system (TMS). Off-road shock is available in Baja, rock crawl, and mud/sand TMS mode. The solenoid-mounted shocks vary fluid pressure. Shocks can increase hydraulic pressure up to 400 lb (181.4 kg), and can increase damping force by up to 400 lb (181.4 kg).

Raptor’s shocks rely on 12 suspension sensors and Ford Performance control algorithms to react to specific driving conditions. During off-road driving, three software control parameters (terrain recognition, loud pedal, and jump mode) elicit real-time damping adjustments.

Terrain recognition monitors front wheel position via the front suspension’s ride height sensors. “When the sensor inputs are very small, shocks are soft. But as the sensor inputs get larger with bigger up and down wheel movements, compression damping occurs to keep the truck from bottoming out,” Paiva said.

Loud pedal control makes adjustments based on front wheel position and accelerator pedal position. “If the driver adds aggressive throttle inputs to the off-road equation, the shocks will get stiffer to prepare for an impact," Paiva explained. "So that basically means the damping force increases to slow the wheel as it comes up vertically, reducing the ‘bump-stop’ strikes.”

Jump mode control also uses the front suspension’s ride height sensors. “If the wheels go to a full rebound/full droop, the vehicle knows it is in the air or it’s getting very, very close to being in the air. When this occurs, the suspension control module commands the shocks to full stiff in order to ‘catch’ the truck when it lands, preventing it from bottoming out,” noted Paiva.

On-road ride control varies with vehicle speed, so softer damping for slow speeds and stiffer damping at highway speeds. The active roll control improves steering feel and precision. When the driver turns into a corner, the outside dampers stiffen to keep the body flat, Paiva said.

Raptor’s ride height sensors are also used in conjunction with the Ford Expedition full-size SUV’s continuously controlled damping, a computer-controlled shock absorber system that adjusts dampers every two milliseconds. Raptor’s vehicle dynamic module, which serves as the shock system’s brains, is packaged on the driver’s side kick panel.

All-new Trail Control debuts on the 2019 Raptor. “It’s like cruise control for off-roading,” said Brandon Cameron, brake controls development engineer for Ford Performance.

Functional in 2-High, 4-High, 4-auto, and 4-low driveline configurations, Trail Control essentially adds a propulsion feature to the prior Raptor’s hill descent control. After pressing a dashboard button to engage Trail Control, the driver sets a speed between 1-20 mph (1.6-31 kph) via the steering wheel’s cruise control button.

If vehicle speed is set at 20 mph (31 kph), but the driver slows the vehicle to 5 mph (8 kph) because of rocky terrain, Trail Control automatically resets the speed to 5 mph (8 kph). “The system doesn’t turn off and force you to turn it back on like [conventional] cruise control,” Cameron explained.

The 2019 F-150 Raptor is powered by a High-Output 3.5L V6 EcoBoost engine (exclusive to Raptor) mated with a 10-speed automatic transmission. The truck goes on sale in late 2018.

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