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Jeep Wrangler JL and Gladiator JT: Performance Modifications
Learn your modification options for the most modern and exciting Jeeps!
Going back to World War II, Jeeps have had a special place in America’s heart. The utility vehicle that helped win the war transitioned into the civilian Jeep, or CJ, and the Jeep brand has had several owners over the years. While still remaining wildly popular, it has evolved. The Wrangler version of the Jeep was transformed with the release of the JK for the 2007 model year. With a more practical 4-door version, this Wrangler became a popular vehicle for year-round use, which appealed to off-roaders as well as soccer moms. For the 2017 model year, Jeep seriously upgraded the Wrangler, which is now dubbed the JL, and added an exciting new model, the Gladiator, or JT, which is essentially a pickup version of the Wrangler.
In Jeep Wrangler JL and Gladiator JT: Performance Modifications, Jeep experts Don Alexander and Quinn Thomas introduce you to these new models and walk you through the capabilities and options for all of the trim levels. Then, they examine how to make these things better, system by system. Suspension, steering, and brakes are covered, as they are the heart of any off-road rig. Also examined are modification options for axles, driveshafts, and differentials as well as bumpers, armor, and protection. Of course, off-roaders need a quality winch, recovery gear, and upgraded electrics, so options are explored here as well. Wheels and tires are also very important for those leaving paved roads, and upgrade options for all of the trim levels and lift levels are covered thoroughly.
Whether you want to build a JL or JT to be a serious rock crawler or simply look like you are going off-road, all of your options are thoroughly explained in this book. Add a copy to your Jeep reference library.
Acknowledgments
Foreword
Chapter 1: A New Jeep Wrangler
Major Differences: Wrangler JK versus Wrangler JL and Gladiator JT
Trim Levels
Off-Road Use
Chapter 2: Modifications
The Key to Pandora’s Box
Items to Consider
Chapter 3: Suspension
Ground Clearance, Angles, and Center of Gravity
Important Lift Considerations
Suspension Travel
Body Lifts
Lift Kits
Tire Size
Spacer Lifts
Spring Lift Kits
Short-Arm Lifts
Long-Arm Lifts
Coilover Lifts
Suspension Control Arms
Track Bars
Suspension Control Arm and Track Bar Joints
Axle Articulation
Sway Bars and Sway-Bar Disconnects
Suspension Alignment
Shock Absorbers
Chapter 4: Steering
How the Steering Works
Death Wobble
Tie-Rods and Drag Links
Ball Joints
Steering Dampers
Stock Steering Box and Pump
Power Steering Upgrades
Chapter 5: Brake Upgrades
Stock Brake Performance
Tire Size Effects on Braking Performance
Large Tires, Pedal Pressure, and Brake Performance
Brake Rotors
Brake Calipers
Brake Pads
Brake Kits
Brake Fluid
Chapter 6: Drivelines, Axles, Housings, Driveshafts, and Lockers
Ring and Pinion Gear Upgrades
Axle Upgrades
Axle Shaft Diameter and Splines
Axle Housing Trusses and Braces
Full Axle Assembly Swaps
Selectable Axle Lockers
Limited-Slip Differentials and Detroit Lockers
Driveshafts, Yokes, CV Joints, and U-Joints
Chapter 7: Off-Road Tires and Wheels
Tire Testing
Results
Off-Road Tire Pressure
Void Ratio and Tread Blocks
Tire Diameter and Ground Clearance
Tire Compliance Over Rocks and Obstacles
All-Terrain versus Mud-Terrain Tires
Ply Ratings, Tire Cutting, and Slashing
Reasons to Air Down Tires
Tire Deflator Types
Airing Up Tires
Wheels
Wheel Diameter
Wheel Width
Bolt Pattern
Offset and Backspacing
Wheel Weight
Wheel and Tire Balancing
Wheel Spacers and Adapters
Chapter 8: Bumpers, Armor, and Protection
Skidplates
Rock Sliders
Body Armor
Fenders
Bumpers
Sport Cage
Chapter 9: Styling, Accessories, Storage, and Overlanding Upgrades
Half and Tube Doors
Tops
Sunshades
Storage Options
Locks
Floor Mats
Roof Racks
Snorkels
Seats and Seat Covers
Graphic Wraps and Touch-up Paint
Other Accessories
Overlanding
Chapter 10: Stock Engines, Upgrades, and Swaps
Upgrades
V-8 Swaps
Chapter 11: Electrical Upgrades and Lights
Auxiliary Switch Solutions
Auxiliary Lighting
Daylight Driving on Dusty Trails
Radio Communications
Satellite Messengers
GPS and GPS Apps
Electronic Calibration Modules
Batteries and Jumper Batteries
Chapter 12: Vehicle Recovery Gear, Winches, and Trail Tools
Tow Strap
Shackles
Kinetic (Yanker) Strap
Extraction Boards
Shovels
Off-Road Jacks
Winches
Winch Line: Wire Rope versus Synthetic
Winch Controllers
Winching Accessories
Chapter 13: Jeep Projects
Don Alexander: 2020 Jeep Wrangler JL Unlimited Sport S
Quinn Thomas: All J Products 2020 Jeep Gladiator JT Rubicon
Appendix: Project Jeep
Specifications
Source Guide
Learn your modification options for the most modern and exciting Jeeps!
Going back to World War II, Jeeps have had a special place in America’s heart. The utility vehicle that helped win the war transitioned into the civilian Jeep, or CJ, and the Jeep brand has had several owners over the years. While still remaining wildly popular, it has evolved. The Wrangler version of the Jeep was transformed with the release of the JK for the 2007 model year. With a more practical 4-door version, this Wrangler became a popular vehicle for year-round use, which appealed to off-roaders as well as soccer moms. For the 2017 model year, Jeep seriously upgraded the Wrangler, which is now dubbed the JL, and added an exciting new model, the Gladiator, or JT, which is essentially a pickup version of the Wrangler.
In Jeep Wrangler JL and Gladiator JT: Performance Modifications, Jeep experts Don Alexander and Quinn Thomas introduce you to these new models and walk you through the capabilities and options for all of the trim levels. Then, they examine how to make these things better, system by system. Suspension, steering, and brakes are covered, as they are the heart of any off-road rig. Also examined are modification options for axles, driveshafts, and differentials as well as bumpers, armor, and protection. Of course, off-roaders need a quality winch, recovery gear, and upgraded electrics, so options are explored here as well. Wheels and tires are also very important for those leaving paved roads, and upgrade options for all of the trim levels and lift levels are covered thoroughly.
Whether you want to build a JL or JT to be a serious rock crawler or simply look like you are going off-road, all of your options are thoroughly explained in this book. Add a copy to your Jeep reference library.
Acknowledgments
Foreword
Chapter 1: A New Jeep Wrangler
Major Differences: Wrangler JK versus Wrangler JL and Gladiator JT
Trim Levels
Off-Road Use
Chapter 2: Modifications
The Key to Pandora’s Box
Items to Consider
Chapter 3: Suspension
Ground Clearance, Angles, and Center of Gravity
Important Lift Considerations
Suspension Travel
Body Lifts
Lift Kits
Tire Size
Spacer Lifts
Spring Lift Kits
Short-Arm Lifts
Long-Arm Lifts
Coilover Lifts
Suspension Control Arms
Track Bars
Suspension Control Arm and Track Bar Joints
Axle Articulation
Sway Bars and Sway-Bar Disconnects
Suspension Alignment
Shock Absorbers
Chapter 4: Steering
How the Steering Works
Death Wobble
Tie-Rods and Drag Links
Ball Joints
Steering Dampers
Stock Steering Box and Pump
Power Steering Upgrades
Chapter 5: Brake Upgrades
Stock Brake Performance
Tire Size Effects on Braking Performance
Large Tires, Pedal Pressure, and Brake Performance
Brake Rotors
Brake Calipers
Brake Pads
Brake Kits
Brake Fluid
Chapter 6: Drivelines, Axles, Housings, Driveshafts, and Lockers
Ring and Pinion Gear Upgrades
Axle Upgrades
Axle Shaft Diameter and Splines
Axle Housing Trusses and Braces
Full Axle Assembly Swaps
Selectable Axle Lockers
Limited-Slip Differentials and Detroit Lockers
Driveshafts, Yokes, CV Joints, and U-Joints
Chapter 7: Off-Road Tires and Wheels
Tire Testing
Results
Off-Road Tire Pressure
Void Ratio and Tread Blocks
Tire Diameter and Ground Clearance
Tire Compliance Over Rocks and Obstacles
All-Terrain versus Mud-Terrain Tires
Ply Ratings, Tire Cutting, and Slashing
Reasons to Air Down Tires
Tire Deflator Types
Airing Up Tires
Wheels
Wheel Diameter
Wheel Width
Bolt Pattern
Offset and Backspacing
Wheel Weight
Wheel and Tire Balancing
Wheel Spacers and Adapters
Chapter 8: Bumpers, Armor, and Protection
Skidplates
Rock Sliders
Body Armor
Fenders
Bumpers
Sport Cage
Chapter 9: Styling, Accessories, Storage, and Overlanding Upgrades
Half and Tube Doors
Tops
Sunshades
Storage Options
Locks
Floor Mats
Roof Racks
Snorkels
Seats and Seat Covers
Graphic Wraps and Touch-up Paint
Other Accessories
Overlanding
Chapter 10: Stock Engines, Upgrades, and Swaps
Upgrades
V-8 Swaps
Chapter 11: Electrical Upgrades and Lights
Auxiliary Switch Solutions
Auxiliary Lighting
Daylight Driving on Dusty Trails
Radio Communications
Satellite Messengers
GPS and GPS Apps
Electronic Calibration Modules
Batteries and Jumper Batteries
Chapter 12: Vehicle Recovery Gear, Winches, and Trail Tools
Tow Strap
Shackles
Kinetic (Yanker) Strap
Extraction Boards
Shovels
Off-Road Jacks
Winches
Winch Line: Wire Rope versus Synthetic
Winch Controllers
Winching Accessories
Chapter 13: Jeep Projects
Don Alexander: 2020 Jeep Wrangler JL Unlimited Sport S
Quinn Thomas: All J Products 2020 Jeep Gladiator JT Rubicon
Appendix: Project Jeep
Specifications
Source Guide
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