Suspension lift

suspension lift is a modification to a vehicle to raise the ride height. It is usually done for the practical purpose of improving the off road performance of SUVs or trucks and other off-road vehicles, or for cosmetic purposes. Suspension lifts can enable steeper approach, departure, and breakover angles, higher ground clearance, and helps accommodate larger wheels and tires. Due to the raised center of gravity, maximum safe operating angles can be reduced and roadholding is often significantly impaired.

Truck with a suspension lift

lift kit is an aftermarket product package with the parts needed to lift a specific model of vehicle, typically with instructions and customer support. Some kits may have only critical or difficult to obtain parts, needing generic or off the shelf hardware and parts to complete the lift. Some lifts need only a few parts, like lift blocks, the spacers placed between the axles and leaf springs, and coil spring/strut spacers and extended shocks, and special driveshafts, axles, and more. More extensive lifts require many new suspension, steering, and drivetrain parts, such as replacement control arms, trailing arms, custom four-link systems, and drive shafts. These changes may be necessary because raising the vehicle’s ride height can impact drive shaft length, steering geometry, and brake lines. Legality is often an issue when installing suspension lifts, as many jurisdictions have varying laws on vehicle ride height and placement of lights and bumpers.

Leaf spring lift

Jeep Cherokee with 2 inch Suspension lift on 31 inch BFG A/Ts, using add-a-leaf and coil spring spacers

Many trucks are supported by leaf spring suspensions. Leaf springs offer exceptional articulation, a large payload and can take a substantial amount of abuse.[citation needed] With the correct methods they can be modified to help a vehicle carry more weight, have better articulation or to fit large oversized tires. Some vehicles may be equipped with front and rear leaf springs or just rear leaf springs with independent front suspension.

Some methods of lifting are good for the rear, but not for the front, such as lifting blocks. Lifting the rear with blocks is a common way to achieve the desired height. This is done by installing a block, of the desired height of lift, in between the leaf spring and leaf spring perch and installing longer U-bolts. It is a bad method for the front primarily because of safety issues while braking. When braking, the front wheels create the majority of the braking force. The block moves this lateral force, caused by braking, higher above the axle than it did in the stock form. This can cause the block to become displaced from its location and result in total loss of control.[1]

A more accepted way to build up the leaf springs is by using an add-a-leaf. This is done by inserting an extra leaf into the vehicle’s leaf pack. Using the add-a-leaf will increase the height, but sometimes makes the suspension ride rough because of the added spring rate.[2] With an adequate budget, the best way to lift with leaf springs is to buy a new set with the lift built in. An add-a-leaf depends on the integrity of the old springs. They may be a bit worn out, so when the lift is installed, the proposed 2 inch leaves may only have lifted the truck 1.5 inches. The new leaf spring pack will not be fatigued and will give the true lift desired. These packs can be bought at various increments of lift and can be combined with lifting shackles to give the proper setup.

Suspension A clutch is a mechanical device which engages and disengages power transmission especially from driving shaft to driven shaft. In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). In these devices, one shaft is typically attached to an engine or other power unit (the driving member) while the other shaft (the driven member) provides output power for work. While typically the motions involved are rotary, linear clutches are also possible. In a torque-controlled drill, for instance, one shaft is driven by a motor and the other drives a drill chuck. The clutch connects the two shafts so they may be locked together and spin at the same speed (engaged), locked together but spinning at different speeds (slipping), or unlocked and spinning at different speeds (disengaged).   Single dry-clutch friction disc. The splined hub is attached to the disc with springs to damp chatter. Friction clutches ...
Self-levelling suspension Self-levelling refers to an automobile suspension system that maintains a constant ride height of the vehicle above the road, regardless of load. Purpose Nose up, tail down attitude of vehicle without self-levelling suspension Many vehicle systems on a conventional vehicle are negatively affected by the change in attitude coming from changes in load - specifically a heavy load in the rear seat or luggage compartment. This change in attitude affects aerodynamic properties, headlight aim, braking, bumpers, shock absorption from the suspension and the vehicle's performance in a collision. Most of the braking power is on the front wheels of a vehicle, which means you will have more effective braking when more weight is over the front wheels. When the rear end has a heavy load, the braking is not as effective. The weight is concentrated on the rear end of the vehicle, and the rear brakes need to do all of the work. When braking quickly in this situation, the front br...
Strut bar A strut bar, strut brace, or strut tower brace (STB) is an automotive suspension accessory usually used in conjunction with MacPherson struts on monocoque or unibody chassis to provide extra stiffness between the strut towers. With a MacPherson strut suspension system where the spring and shock absorber are combined in the one suspension unit which also replaces the upper control arm, the entire vertical suspension load is transmitted to the top of the vehicle's strut tower, unlike a double wishbone suspension where the spring and shock absorber may share the load separately. In general terms, a strut tower in a monocoque chassis is a reinforced portion of the inner wheel well and is not necessarily directly connected to the main chassis rails. For this reason there is inherent flex within the strut towers relative to the chassis rails. A strut bar is designed to reduce this strut tower flex by tying the two strut towers together. This transmits the load off each strut to...
Active suspension Active suspension is a type of automotive suspension that controls the vertical movement of the wheels relative to the chassis or vehicle body with an onboard system, rather than in passive suspension where the movement is being determined entirely by the road surface. Active suspensions can be generally divided into two classes: pure active suspensions, and adaptive/semi-active suspensions. While adaptive suspensions only vary shock absorber firmness to match changing road or dynamic conditions, active suspensions use some type of actuator to raise and lower the chassis independently at each wheel. These technologies allow car manufacturers to achieve a greater degree of ride quality and car handling by keeping the tires perpendicular to the road in corners, allowing better traction (engineering) and control. An onboard computer detects body movement from sensors throughout the vehicle and, using data calculated by opportune control techniques, controls the action of the active and...
Beam axle A beam axle, rigid axle or solid axle is a dependent suspension design, in which a set of wheels is connected laterally by a single beam or shaft. Beam axles were once commonly used at the rear wheels of a vehicle, but historically they have also been used as front axles in rear-wheel-drive vehicles. In most automobiles, beam axles have been replaced by front and rear independent suspensions. Beam axle and Panhard rod on a 2002 Mazda MPV Implementation Solid axle suspension characteristics: Camber change on bumps, none on rebound, large unsprung weight With a beam axle the camber angle between the wheels is the same no matter where it is in the travel of the suspension. A beam axle's fore & aft location is constrained by either: trailing arms, semi-trailing arms, radius rods, or leaf springs. The lateral location is constrained by either: a Panhard rod, a Scott Russell linkage or a Watt's linkage. While shock absorbers and either leaf springs, c...