ReadyLIFT 2.0" Cast Iron Rear Block Kit | 2011–2024 GM 2500/3500 HD Trailer Package & Dually

ReadyLIFT 2.0" Cast Iron Rear Block Kit | 2011–2024 GM 2500/3500 HD Trailer Package & Dually

Is This for You?
You're running a 2011–2024 GM 2500 HD Single Rear Wheel with the factory Trailer Package rear springs, or a 3500 HD Dual Rear Wheel truck, and you need 2" of rear lift to restore rake for towing and hauling — or to level out a front leveling kit. You need OEM-quality cast iron construction, not lightweight extrusions, and U-bolts sized specifically for the trailer package and dually rear suspension geometry. The ReadyLIFT 66-3020 is built to the same standard as the factory blocks, backed by a Lifetime Warranty.

The Result
Two OEM-style cast iron rear lift blocks at 2.0" height — manufactured from cast iron just like the factory blocks for maximum strength and reliability, never from lightweight extrusions. Four new longer e-coated U-bolts with nuts and washers are sized specifically for the trailer package and dually rear suspension. The result is 2" of rear lift that restores a purposeful towing rake, pairs perfectly with any ReadyLIFT leveling kit, and carries a Lifetime Warranty.

Verified Fitment (OFAS Standard)
✅ Fits: 2011–2024 GM Silverado/Sierra 2500 HD Single Rear Wheel (SRW) with factory Trailer Package rear springs (2WD and 4WD)
✅ Fits: 2011–2024 GM Silverado/Sierra 3500 HD Dual Rear Wheel (DRW/Dually)
❌ Does NOT fit: 2500 HD trucks equipped with top-mounted overload springs — confirm spring configuration before ordering
❌ Does NOT fit: 2500 HD trucks without the factory Trailer Package rear springs
❌ Does NOT fit: 2010 and earlier GM HD platforms

Wheel & Tire Fitment
No wheel or tire restrictions specific to this component. Verify your total lift height and tire clearance with your existing front lift configuration before ordering.

Installation & Engineering Notes
This is a bolt-on rear block kit requiring no cutting or welding. U-bolts must be torqued to OEM specification at ride height. Do not use this kit on 2500 HD trucks equipped with top-mounted overload springs — the block geometry is not compatible with that spring configuration. A professional alignment check is recommended after installation to confirm ride height. Lifting your vehicle raises its center of gravity; exercise appropriate caution when towing or hauling. All Advanced Driver Assistance Systems (ADAS) including GM Safety Alert Seat and automatic headlight leveling should be verified after any suspension height change.

Engineering Question: Is your GM HD a 2500 SRW with the factory Trailer Package rear springs, or a 3500 DRW? And does your 2500 HD have top-mounted overload springs? Confirm your rear spring configuration and axle setup before ordering — this kit is not compatible with top-mounted overload spring applications.