Rough Country 256.20 — 4 Inch Lift Kit | Rear Springs | Chevy/GMC C10/K10 Truck & SUV/K5 Blazer (77-91).

About this part

Transform Your Truck's Stance and Capability: Upgrade your GM truck from front to back with Rough Country's 4" Suspension Lift Kit. This premium lift delivers a leveled, aggressive look while enhancing ride height and off-road readiness all with an easy bolt-on installation. Engineered for Superior Ride Quality: This kit includes application-specific front lifted leaf springs, delivering increased ground clearance without sacrificing ride comfort or control. Rear lift blocks and brake line brackets maintain proper geometry, ensuring a smooth, factory-like ride after installation. For a complete suspension upgrade, the kit is also available with replacement rear lifted leaf springs, offering consistent rear lift and eliminating the need for lift blocks. Enhanced Performance with N3 Series Shocks: Rough Country's N3 series shocks come standard valved for your exact application and designed to provide a perfect balance of on-road smoothness and off-road capability. Featuring a 10-stage variable valving system, high-pressure nitrogen charge, and durable 54mm shock body with 18mm piston rod, these shocks are built for performance and longevity. Room for Bigger Tires: Make room for aggressive wheel and tire combos. This 4" lift offers enough clearance to run up to a 35" tall tire with proper backspacing, giving your truck the rugged stance it deserves. Improved Steering and Handling: To maintain proper drivability, a raised steering arm is included correcting steering geometry for tight, responsive handling after the lift. Limited Lifetime Warranty: Rough Country backs this kit with a Limited Lifetime Warranty, giving you long-term confidence on and off the road.

Manufacturer features

Boosted Ground Clearance: Gain the extra height needed for better off-road capability and obstacle clearance. Application-Specific Front Leaf Springs: Engineered for a perfect fit and optimal ride quality. Optional Rear Leaf Springs: Available with replacement rear springs for a complete suspension upgrade. Clears 35-Inch Tires: Provides ample room to run up to a 35" tall tire with no rubbing. Raised Steering Arm Included: Corrects steering geometry for precise handling and improved alignment. Premium N3 Series Shocks: Includes application-valved N3 shock absorbers for balanced on-road comfort and off-road control.

Important application and installation requirements

ONLY fits models with 56" rear leaf springs. If vehicle is equipped with a front sway-bar, drop brackets are recommended SKU: 1019 . Optional Rear Springs: To confirm rear spring size a measurement will have to be pulled from eyelet to eyelet. For a visual, please click here . Vehicles with factory quad shocks (2 front shocks per side) will simply use a single aftermarket shock.

Manufacturer-listed applications

1977-1987:4WD:Chevy:C10/K10 Pickup;1977-1987:4WD:GMC:C15/K15 Pickup;1977-1991:4WD:Chevy:C10/K10 Suburban;1977-1991:4WD:Chevy:K5 Blazer;1977-1991:4WD:GMC:C15/K15 Suburban;1977-1991:4WD:GMC:Jimmy

Read the complete trim, drivetrain and installation restrictions. Application records are manufacturer supplied; they are not an independent fitment certification.

Manufacturer installation instructions

Manufacturer part number: 256.20. Shipping weight: 289.20lbs. Supplier shipping classification: Ground Only.

Rough Country product specifications and restrictions

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