A full complement of heavy-duty suspension, chassis, steering, drivetrain, and high-performance engine parts has been developed for this platform. Jeep Wrangler JK 2007-Present: Performance Upgrades co-authors Don Alexander and Quinn Thomas offer guidance for making those modifications. Lift kits from 1.75 to 5 inches are available, so you can fit off-road wheels and tires for exceptional traction. Suspension springs, specially calibrated coilover shocks, and sway bars must work in concert to provide the correct suspension articulation and ride quality to scale obstacles and negotiate terrain. To increase durability and essential reliability, pitman arms, drop links, driveline parts, steering boxes, and skid plates are examined. Because the drivetrain must be ready for off-road service, the authors cover the most rugged and reliable axle assemblies available. Exhaust, intake, and electronic engine mapping upgrades make the Jeep 3.6- and 3.8-liter V-6 engines much more potent. This book also includes information on swapping GM LS and new Hemi engines into the JK for vastly improved performance.
Since its release in 2007, the JK has become wildly popular and nearly 1 million units have been sold in North America. With a wider track and longer wheelbase, the Wrangler JK is roomier, more comfortable, and delivers better on-road performance than its predecessor. However, it needs serious chassis, suspension, and drivetrain upgrades to tackle demanding off-road terrain and rock crawling.
If you believe that paved roads are simply access-ways to the open range, you and your JK need this book. It contains the valuable information to convert any mild-mannered street vehicle into an all-conquering off-road rig. Whether it’s lift kits, wheels, tires, drivetrain, or suspension and engine parts, this volume provides detailed information and insightful guidance so you can build an off-road JK to handle the toughest terrain.r
A full complement of heavy-duty suspension, chassis, steering, drivetrain, and high-performance engine parts has been developed for this platform. Jeep Wrangler JK 2007-Present: Performance Upgrades co-authors Don Alexander and Quinn Thomas offer guidance for making those modifications. Lift kits from 1.75 to 5 inches are available, so you can fit off-road wheels and tires for exceptional traction. Suspension springs, specially calibrated coilover shocks, and sway bars must work in concert to provide the correct suspension articulation and ride quality to scale obstacles and negotiate terrain. To increase durability and essential reliability, pitman arms, drop links, driveline parts, steering boxes, and skid plates are examined. Because the drivetrain must be ready for off-road service, the authors cover the most rugged and reliable axle assemblies available. Exhaust, intake, and electronic engine mapping upgrades make the Jeep 3.6- and 3.8-liter V-6 engines much more potent. This book also includes information on swapping GM LS and new Hemi engines into the JK for vastly improved performance.
Since its release in 2007, the JK has become wildly popular and nearly 1 million units have been sold in North America. With a wider track and longer wheelbase, the Wrangler JK is roomier, more comfortable, and delivers better on-road performance than its predecessor. However, it needs serious chassis, suspension, and drivetrain upgrades to tackle demanding off-road terrain and rock crawling.
If you believe that paved roads are simply access-ways to the open range, you and your JK need this book. It contains the valuable information to convert any mild-mannered street vehicle into an all-conquering off-road rig. Whether it’s lift kits, wheels, tires, drivetrain, or suspension and engine parts, this volume provides detailed information and insightful guidance so you can build an off-road JK to handle the toughest terrain.r
Acknowledgments
About the Authors
Introduction
Chapter 1: Wheels and Tires
All-Terrain Versus Mud-Terrain
Off-Road Tire Performance
Tire Size, Diameters, and Ground Clearance
Off-Road Tests
On-Road Tests
Wheels and Tires
Chapter 2: Suspension, Lifts, and Steering
Lifting for Off-Road Clearance
Suspension Springs
Suspension Control Arms
Track Bars
Shock Absorbers
Anti-Roll Bars and Articulation
Steering System
Suspension and Steering Alignment
Jeep JK Profile: Fabtech Motorsports’s 2014 Wrangler JK Unlimited Rubicon
Chapter 3: Brake Upgrades
Increase Brake Performance
Brake Rotors
Brake Calipers
Brake Master Cylinders
Brake Pads
Brake Kits
Brake Flex Lines
Brake Fluid
Jeep JK Profile: Heather and Quinn Thomas’s All J Products 2007 JK Unlimited Hemi
Chapter 4: Bumpers, Armor, and Protection
Skidplates
Rock Sliders
Body Armor
Door Options
Fenders
Tire Size
Modifying Stock Fenders for Clearance
Front Bumpers
Rear Bumpers
Jeep JK Profile: John and Cinde Angelastro’s sPOD JK
Chapter 5: Drivelines, Axles, and Lockers
Tire Size versus Ratio
Ring and Pinion Gear Upgrades
Axle Upgrades
Axle Housing Reinforcements
Full Axle Assembly Swaps
Axle Lockers
Limited-Slip and Detroit Lockers
Driveshafts, Yokes, CV Joints, and U-joints
Jeep JK Profile: John Currie’s 2015 Jeep Wrangler JK Unlimited
Chapter 6: Engines, Engine Swaps and Transmissions
Cold-Air Intakes
Performance Exhausts
Engine Tuners
Superchargers
Turbochargers
Air-Intake Snorkels
Engine Swaps
Transmission and Cooling Systems
Heavy-Duty Clutch Kits
Automatic Transmissions 1
Cooling System
Jeep JK Profile: Norbert “Nobby” and Deanna Schnabel
Chapter 7: Styling and Storage Upgrades
Aftermarket Tops
Sun Shades
Tube Doors
Half Doors
MOLLE System Soft-Bag Storage
Metal Storage Boxes
Interior Storage
Fluid Storage
Door Hinges and Stops
Mirrors
Roof Racks
Mud Flaps
Jeep JK Profile: GenRight Terremoto Jeep JK
Chapter 8: Electrical and Lights
Battery Upgrades
Battery Cables and Terminals
Auxiliary Lighting
Jeep JK Profile: Ray Currie’s 2007 JK Unlimited
Chapter 9: Winches, Vehicle Recovery Gear, and Trail Tools
Selecting a Winch
Winch Accessories
Ground Anchor for Winching Extraction Boards, Sand Ladders, and Bridging Ladders
Trail Tools and Spare Parts
Fluid Storage
Tire Repair Kit
Spare Parts
GPS Systems
Jeep JK Profile: Don Alexander’s Jeep 4x4 School 2013 JKU Grizzlycon
Source Guide