The RE7324 4.5 inch Extreme Duty Long Arm System is the first and only radius long arm suspension available for the Jeep JK. This system features our world class chromoly radius arm both in the front and in the rear. Geometry has been meticulously engineered to keep pinion and driveshaft angles in phase, while eliminating jacking and unwanted suspension squat. Engineered radius arm suspension with properly valved Rubicon shocks correctly allows the JK to transmit throttle input to the wheels and over varied terrain, providing forward progress instead of getting stopped due to unwanted compression response.This suspension will allow the use of 37 inch tiresNOTE: Front and rear driveline modifications will be required.WHEEL RECOMMENDATIONS: 8" or 10" wide wheels with a 4.5" backspacing. ComponentsRE1143 - GEN2 DISCONNECTS 3.5"-5.5" JKRE1157 - JK REAR SWAY BAR LINKSRE1371 - JK 3.5" 4DR / 4.5" 2DR FT COILRE1376 - JK 3.5" 4DR / 4.5" 2DR RR COILRE1380 - BUMPSTOPS 2" FRONT LOWERRE1387 - JK REAR 2" BUMP PADRE1530 - JK FRONT BRAKE LINE SET-24"RE1540 - JK REAR BRAKE LINE SET - 20"RE1675 - JK FRONT TRACK BAR BRACKETRE1680 - JK FRONT EX DUTY ADJ. TRACK BARE2610 - JK CHROMOLY DRAG LINKRE4070 - JKLA FRONT LEFT LOWER ARMRE4075 - JKLA FRONT UPPER ARMSRE4080 - JKLA FRONT RIGHT LOWER ARMRE4085 - JKLA REAR LEFT LOWER ARMRE4090 - JKLA REAR UPPER ARMSRE4095 - JKLA REAR RIGHT LOWER ARMRE4520 - JKLA FRONT CROSSMEMBER ASSYRE4525 - JKLA REAR CONTROL ARM MOUNTS