Rear Lift Blocks

Installation Guide | Apoc Industries | Universal — All Makes and Models

Overview

This guide covers the installation of Apoc Industries rear lift blocks. Lift blocks are used to raise the rear of the vehicle by replacing the factory block between the leaf spring and axle with a taller block. The installation process is essentially the same across all makes and models.

Kit Contents

• 2x Rear lift blocks (driver and passenger side) — bump stop extensions are welded directly to the block if your kit includes them
• U-bolts and hardware (if included with your kit)
• Anti-wrap bolts (if included with your kit) — 3/8" diameter U-bolts that pass through the holes on the outer edges of the top of the block

Pre-Install Checklist

Required Tools

• Floor jack and jack stands
• Torque wrench
• Socket set — metric and standard
• Safety glasses, gloves, and steel-toed boots (PPE)

Safety Warnings

⚠ Always support the vehicle securely on jack stands before working under it. Never rely solely on a floor jack. Keep a floor jack under the rear differential/pinion throughout this installation to prevent the axle from rotating when the U-bolts and blocks are removed.

Step-by-Step Installation Sequence

Step 1 — Lift the Rear of the Vehicle

• Lift the rear of the truck high enough to relieve tension from the U-bolts — you need enough clearance to remove the old blocks and install the new taller ones
• Place jack stands under the frame for safety
• Position a floor jack under the rear differential/pinion with light upward pressure — this prevents the axle from rotating when the U-bolts and block are removed

Step 2 — Remove the Factory U-Bolts and Old Lift Block

• Loosen and remove the U-bolt nuts and U-bolts
• Remove the old lift block from between the leaf spring and axle
• Keep the floor jack under the pinion to maintain axle position throughout

Step 3 — Install the New Lift Block

⚠ Block orientation is critical — read carefully before installing.

• The lift block has a tapered design — the shorter side with the steeper angle goes to the front of the vehicle and the taller side with the more gradual angle goes to the rear
• If your block has bump stops, they are already welded to the block — orient them so they face inward toward the center of the differential
• Seat the block between the leaf spring and axle — verify the centering pin on the leaf spring seats fully into the hole on top of the block. The block must be fully and squarely seated on the leaf spring — do not proceed if it is not fully engaged
• Verify the centering pin on the bottom of the block seats fully into the hole on the axle pad and the leaf spring is resting squarely on the axle

Step 4 — Install the Anti-Wrap U-Bolts (If Included)

If your kit includes anti-wrap bolts, install them before the main U-bolts:

• The anti-wrap bolts are 3/8" diameter U-bolts — they are smaller than the main U-bolts
• Pass each anti-wrap U-bolt down through the holes on the outermost edges on top of the block — one on each outer edge
• Install the nuts on the underside and snug them down to hold the block firmly in place — do not fully torque yet

Step 5 — Install the Main U-Bolts

The main U-bolts do not go through any hole in the block:

• The main U-bolts simply slide down the sides of the block and clamp around the axle tube
• Place the U-bolt plate under the axle and thread the nuts onto the U-bolt legs through the axle plate
• Snug the nuts evenly — do not fully torque yet
• With everything snugged, do a final check that both centering pins — top and bottom — are still fully seated

Step 6 — Repeat on the Opposite Side

• Repeat Steps 3–5 on the opposite side before torquing either side
• Confirm both blocks are correctly oriented and fully seated on both sides before proceeding

Step 7 — Lower to Ride Height and Torque U-Bolts

• Lower the vehicle to the ground so the full weight of the truck is on the wheels
• Torque all main U-bolt nuts to your vehicle's factory U-bolt torque specification — this varies by make, model, and U-bolt size and must be looked up for your specific vehicle. Refer to your factory service manual or a trusted torque spec resource
• Torque in a cross pattern to ensure even clamping
• Torque the anti-wrap U-bolt nuts if applicable
• Mark all torqued fasteners with a torque stripe for visual verification

Driveline Angle Notes

The compound taper built into Apoc Industries lift blocks is designed to correct driveline angles for the lift height of the block. In most cases no additional driveline correction is needed. However, if you experience vibration after installation, check your driveshaft angles.

💡 One-Piece Driveshaft: For correct driveline geometry, the pinion angle and the transfer case output yoke angle should be equal and opposite — if you were to draw a line through the center of the pinion and a line through the center of the transfer case yoke, those two lines should be parallel. The block taper is designed to achieve this for the corresponding lift height. If vibration is present, verify these angles are parallel before looking at other causes.

💡 Two-Piece Driveshaft: If you experience launch shudder or vibration under acceleration after installing lift blocks, the carrier bearing angle may need correction. A carrier bearing drop bracket may be required to bring the carrier bearing back into the correct angle range. Contact Apoc Industries if you need assistance selecting the correct carrier bearing drop for your application.

Post-Install Notes

• Re-check all U-bolt torque after 50–100 break-in miles — U-bolts can settle after initial installation
• Inspect all hardware for loosening at each oil change interval
• If vibration is present after installation, verify driveshaft angles before assuming a driveline component issue

Safety Disclaimers

This installation guide is provided for reference purposes. Apoc Industries assumes no liability for improper installation, use of incorrect torque values, or failure to follow all safety procedures. Always torque U-bolts to your vehicle manufacturer's specification. Suspension modifications affect vehicle handling and stability — always have suspension work inspected by a qualified mechanic and comply with all local laws regarding vehicle modifications and lift height limits.

Apoc Industries | apocindustries.com | Document Version: v1.0