Complete collection of Jeep and off-road trails in the Las Vegas area

Jeep Glossary


Being around Jeeps for so many years you tend to get used to the slang and terms of 4 wheeling. In case you are wondering what all these terms mean, please refer to the Jeep glossary we have provided.


Air-down

A term used when deflating tires. Usefull for traverseing ruggest terrain. It provides more surface area for the tire obtain tracktion.

Approach Angle

Starting from level ground, this is the degree of slope a vehicle can approach without scraping or hitting the front undercarriage. It's a great indication of the ability to navigate severe off-road terrain like boulders and logs. A short front overhang produces high angles of approach, thus increasing off-road ability.

Articulation

The ability of one axle to move relative to the chassis. It is the measure of the ease with which tires stay in contact with the ground (and retain traction) on very uneven terrain.

Axle

A rigid piece of metal that connects the front and/or rear wheels together. The suspension components attach to the axle and to the vehicle's body frame.

Axle Differential

An axle differential is a gear system located in the center housing of an axle assembly designed to allow the wheels to rotate at different speeds during cornering.

Ball Joint

A type of connection used on suspension systems, especially steering systems that allow movement in any direction

Brake Traction Control System

Transfers torque from one wheel to another on the same axle when wheel slip conditions are detected.

Breakover Angle

The degree of slope that defines the largest ramp or hill that a vehicle can travel over without scraping against the frame or underbody components.

Bushing

A rubber ring designed to take the stress of moving parts and to cushion moving parts. Usually found on control arms and other suspension parts.

Center Differential

A gear system located inside the transfer case of full-time 4x4 vehicles. It is used to distribute drive torque to the front and rear driveshafts and allows the front and rear wheels to rotate at different speeds during cornering.

Clevis Slip Hook

A type of hook typically attached to the cable of a winch used to attach to recover points or other recovery cables. Typically has a spring loaded latch to prevent it from detaching during use.

Clutch Plates

A series of alternating steel plates within the transfer case of many on-demand or automatic 4x4 systems. One set of plates is splined to the clutch assembly hub of the rear driveshaft; the other set is splined to the clutch drum attached to the front driveshaft. The clutch housing is usually filled with a viscous, silicone-type fluid that clings to the discs and, when heated by the friction of slipping, instantly expands to help transfer torque. The engagement of clutch plates can also be controlled electronically.

Coil Springs

A coil of flexible metal that can be compressed or stretched along its centerline axis without permanent deformation. Coil springs support the weight of the vehicle while allowing the wheels to travel up and down over bumps.

Continuously Variable Transaxle

A stepless transmission that uses a sheave clutch to transmit engine torque.

Control Arm

Connects the axle to the frame. Provides the axle the ability to move up and down in relation to the frame.

Crawl Ratio

Essential for serious off-road treks involving steep hill climbs and descents, this is the final drive ratio of a vehicle in Low-Range and in lowest gear. It allows Jeep vehicles to creep along (without depressing the accelerator) at very low speeds. Essentially, the vehicle does all the work. Crawl ratio is determined by this formula: first gear ratio x rear axle ratio x Low-Range 4x4 ratio. The higher the number, the better the off-road capabilities.

Crow Hop

Vehicle shudder and tire scuffing due to a binding condition in the driveline. Usually caused by operating in basic 4x4 or part-time 4x4 modes on dry pavement.

D-Shackle

A shackle commonly used in Jeep recovery. It can couple a winch cable, recovery strap, tree saver, etc. together.

Death Wobble

A horrifying condition where the axle wobbles uncontrollably due to loose or old suspention components.

Departure Angle

When returning to level ground from a descent, this angle indicates the degree of slope from which a vehicle can depart without scraping or hitting the rear undercarriage.

Differential

A gear system that transmits torque to the drive wheels, while also allowing the wheels to rotate at different speeds when cornering. 4x4 vehicles have differentials in both the front and rear axles.

Drag Link

Bar that connects the steering to the axle - pushes and pulls from the steering box to move the tires left and right for steering.

Driveshaft

Shaft connecting the transmission output shaft to the differential drive pinion shaft. Four-wheel-drive vehicles employing this system add a second driveshaft from the transfer case to the front differential.

Electronically controlled Coupling

Manages the torque split from front to rear with no driver input needed for smooth and automatic performance.

Fairlead

A set of rollers that guide the cable from the winch back on to the spool

Fixed Yoke Output Assembly

Effectively handles the extra output from the transfer case and helps to ensure smooth and durable driveline operation.

Four-Wheel Drive

A drivetrain that utilizes a transfer case to distribute engine power between the front and rear axles in order to drive all four wheels. Full-time four-wheel-drive systems utilize a center differential, which enables the front and rear driveshafts to turn at different speeds, thereby allowing engagement on dry pavement for normal driving conditions. A part-time system does not employ a center differential and, during normal driving conditions, must operate only in two-wheel drive. With a part-time system, the four-wheel-drive mode is to be used only when off-road or on wet or slippery surfaces.

Front Axle Disconnect

A mechanical or vacuum-operated component used primarily on four-wheel-drive models to connect and disconnect drive torque to the front axle. When shifting from four-wheel drive to two-wheel drive, this system disengages the front axle from the front driveline, so that the front wheels aren't turning the front driveline unnecessarily. This reduces unnecessary front driveline wear, noise and fuel consumption.

Gearing

The ratio at wich your tire rotated versus the drive shaft. Larger tires require a higher ratio in to order to properly turn the tires.

Ground Clearance

Jeep height so that rocks and uneven ground can be traversed without sustaining undercarriage damage.

Hand Throttle

A device for allowing the driver to throttle the engine with his hand rather than the foot.

Hawse Fairlead

A fairlead that does not use rollers rather it has smooth edges on all sides which guides a cable back on to the spool of a winch. Typically used with synthetic ropes

Hi-Lift Jack

A jack that is designed to lift Jeeps up higher than an ordinary jack.

High-Range

A 4x4 mode used for on-road or light off-road use.

Hill Descent Control

This system uses the antilock brake system braking to control the car's motion downhill. Also allows a smooth and controlled hill descent in rough terrain without the driver needing to touch the brake pedal. If the vehicle accelerates without the driver input, the system will automatically apply the brakes to slow down to the desired vehicle speed.

Jounce/Rebound

The motion of a wheel that compresses its suspension. If a wheel is at full jounce, it is at the upper limits of its travel. The opposite of jounce is rebound - or wheel movement that decompresses a vehicle's suspension.

Knuckle

Part of the steering system that is connected to the front axle. Connects the tie rod to either side.

Limited-Slip Differential

Provides the same basic functions as an axle differential, but with an added advantage: when the drive wheel begins spinning as a result of being on a slippery surface, a limited-slip differential automatically transfers torque to the opposite wheel to help improve traction.

Locking Differential

Provides consistent traction by "locking" the axle shafts together when the driver wants to do it. Locking differentials do not allow for wheel speed differences and must not be used on dry, paved roads.

Long Arm

Control arms that are longer than stock control arms. Provides better articulation, especially for lifted Jeeps

Low Crawl Speed

The crawl ratio is the lowest gear ratio in a vehicle and is determined by multiplying the first gear ratio by the low-range ratio and the axle ratio.

Low-Range

A 4x4 mode used for severe off-road conditions.

Maneuverability

Ability to traverse narrow gaps, dodge emergency situations and avoid cosmetic damage to underbody sills thanks to precision steering and optimized wheelbases.

Neutral

When the shifter is in this position, the front and rear axles spin freely. Sometimes used for towing a Jeep vehicle behind another vehicle (such as a motor home), so that uncoupling the driveshafts is not required. Also used in the process of shifting into 4-Low.

Open-Center Differential

Located in the transfer case on some full-time four-wheel-drive vehicles, this component works in the same way as an open differential in the axles, but is of a more compact design. This component employs a planetary gearset, with planetary gears that revolve around the sun gear and inside the ring gear.

Pitman Arm

Short bar that connect the drag link to the steering box

Power-Robbing Friction

Surface resistance to relative motion, as of a body sliding or rolling.

Rock Slider

Typically metal rails on the side of a Jeep that help prevent damage to the body when rock crawling.

Running Ground Clearance

The distance from the ground to the lowest point between the axles.

Safety Thimble

Winch attachment to replace the standard hook. Called safety because it is supposed to prevent your hand from getting pinched in the fairlead.

Shift-on-the-Fly

The ability to shift from two-wheel drive to four-wheel drive while the vehicle is moving.

Skid Plate

Helps protect the undercarriage from damage when driving off-road.

Slip Yoke Eliminator (SYE)

After market part that replaces the yoke on the rear drive shaft and converts it to U-Joints. Used when lifting a Jeep as the drive line angle increases.

Solid Axle/Coil Springs

Ideal off-road equipment. Instead of each wheel on an axle being sprung separately (like independent suspension designs), a solid axle connects the suspension of two wheels. Coil springs then support the vehicle's weight and allow the wheels to travel up and down over terrain.

Spotter

A person who typically stands outside and directs the driver of a Jeep how to navigate over an obstacle on a trail

Steering Stabilizer

A shock absorber on the steering system that help provide smoother steering

Stinger

Added to the front bumper of a Jeep that helps prevent front rollovers.

Suspension Travel

From full jounce to full rebound, this is the amount of vertical wheel movement allowed by the suspension.

Sway bar

More correctly it is an anti-sway bar. Used to secure the axle to the frame to help roll when turning. The anti-sway bar is ofthen disconnected in off-raod Jeeps which provides better articulation.

Synthentic Rope

Winch cable that is made of synthetic plastics rather than steel. It is lighter and safer due to the fact that if it breaks, it will will not whip and cause damage to person or property.

Tie Rod

A bar connecting the two front tires used in the steering system

Tow Hooks

Heavy-duty forged steel hooks in the front and rear of a vehicle that provide attachment points for snatch-em straps and winch cables should you get stuck.

Track Bar

A bar connecting the frame to the axles, used to keep the frame centered on the axle.

Traction

Traction in 4x4 is equivalent to grip on Asphalt. Traction helps you stay in control on untamed terrain, slippery (wet, mud, snow) conditions and on steep grades.

Transfer Case

Mounted behind and driven by the vehicle transmission, the transfer case transmits power to the front and rear driveshafts in 4x4 Jeep vehicles and offers high and low range.

Transmission

A mechanism that transfers torque into usable driving power through the use of gear sets. These gear sets multiply engine torque in varying amounts to meet specific driving demands.

Tree Saver

A short and fat recovery strap designed to wrap around a tree when winching to spare the tree damage.

Two-Wheel Drive

When the shifter is in this position, the front axle spins freely while power is sent to the rear axle and wheels, which then drive the vehicle.

U-Joint

A universal joint (universal coupling, U-joint, Cardan joint, Spicer or Hardy Spicer joint, or Hooke's joint) is a joint or coupling in a rigid rod that allows the rod to "bend" in any direction, and is commonly used in shafts that transmit rotary motion

Viscous Coupling

A speed-sensitive device located in the transfer case that transmits drive torque between the front and rear driveshafts when wheel slip occurs. Viscous couplings are typically used on all-wheel-drive vehicles and vehicles with automatic and on-demand four-wheel-drive systems.

Winch

Device typically attached to the front of a Jeep that has a spooled cable. A winch can help pull a Jeep out of a stuck situation. The cable is unspooled, attached to solid object like a tree or other Jeep and when turned on, will wind the cable back in to the spool pulling the Jeep along with it.