Universal Lowering Blocks with Fitting Position Rear Axle

Nolathane universal lowering blocks provide a straightforward way to reduce rear ride height on vehicles with leaf spring suspension. Fitted between the leaf spring and the axle, leaf spring lowering blocks drop the body closer to the axle without replacing or re-setting the springs, making them a practical option for pick-ups, classic cars, light commercials and custom builds.

Each listing shows the block height, dimensions and kit contents, so you can match the lowering blocks to your spring width, centre pin and axle perch before ordering.

How Lowering Blocks Work

On a leaf-sprung axle, the spring is clamped to a perch on the axle housing with U-bolts and located by a centre pin that passes through the spring pack. A lowering block fits into that stack, changing the distance between the spring and the axle.

On vehicles where the axle sits on top of the spring (spring-under), the block is fitted between the spring and the axle to lower the vehicle. On spring-over setups, where the spring sits on top of the axle, lowering usually requires a different approach, such as relocating the axle or changing the springs. The block?s own centre pin hole and locating pin keep the spring, block and axle aligned once the U-bolts are tightened.

Because the spring itself is unchanged, its rate and load-carrying characteristics stay the same. Only the static ride height changes.

Why Choose Lowering Blocks for Leaf Springs

Lowering blocks remain one of the simplest ways to lower a leaf-sprung vehicle. Common reasons to fit them include:

• Achieving a lower stance on a pick-up, light truck or classic car without replacing the springs.
• Correcting a rear that sits higher than the front after changes to front suspension.
• Lowering the centre of gravity to reduce body roll for improved on-road handling.
• Restoring a period-correct ride height on a restoration or custom build.
• Matching the rear to a lowered front end for a level stance.

Choosing Universal Lowering Blocks

Lowering blocks are selected by their dimensions, so careful measurement is essential before ordering.

Block Height

The block height sets how much the vehicle will drop. Choose the smallest height that achieves the desired stance, as taller blocks increase leverage on the spring and axle.

Width and Length

The block must match the width of the leaf spring and the size of the axle perch so it sits flat with full contact. A block narrower than the spring will not support it properly, and one that is too wide may not clear the U-bolts.

Centre Pin Fitment

The block must accept the spring?s centre pin head on one side and locate in the perch on the other. Check the centre pin diameter and the locating pin on the block match the spring and axle.

Flat or Tapered Blocks

Some blocks are flat, while others are tapered to change the angle of the axle. A tapered block can help correct pinion angle when ride height changes, keeping the tailshaft (driveshaft or propshaft) universal joints operating at suitable angles.

Fitting Lowering Blocks

Support the vehicle securely on stands under the chassis and support the axle with a jack. Work on one side at a time so the axle stays located. Loosen and remove the U-bolts, lower the axle slightly and fit the block between the spring and the perch, making sure the centre pin and locating pin seat correctly.

Lowering blocks almost always require longer U-bolts, as the original bolts will not have enough thread to clamp the taller stack. Always fit new U-bolts and nuts of the correct length, diameter and grade, as U-bolts stretch when tightened and should not be reused. Tighten the nuts evenly in a cross pattern to the manufacturer?s torque specification, then re-check them after the first few hundred kilometres as the stack settles.

After fitting, check clearances between the axle, chassis, exhaust and fuel tank at full compression, and check the length of brake hoses and ABS sensor wiring at full extension.

Effects on Suspension and Driveline

Lowering a leaf-sprung axle changes more than just ride height, so it is worth planning for the knock-on effects:

• Bump travel: With the body closer to the axle, the suspension has less room to compress. Bump stops may need to be adjusted or replaced to prevent the axle striking the chassis.
• Shock absorbers: Shorter ride height compresses the shock absorber further. Check it does not reach full compression before the bump stop engages.
• Pinion angle: Changes to ride height can alter the axle?s pinion angle and the tailshaft angles, causing vibration. Tapered blocks or adjustments may be needed.
• Load-sensing brake valve: Many pick-ups and light commercials use a load-sensing proportioning valve that adjusts rear brake pressure based on ride height. Lowering can affect how it operates, so it should be checked and adjusted.
• Axle wrap: Taller blocks increase the leverage that acceleration and braking forces apply to the spring, which can lead to axle wind-up or wheel hop.

Limitations and Trade-Offs

Lowering blocks are a cost-effective option, but they are not suited to every vehicle. Blocks reduce available suspension travel, which may make the ride firmer over large bumps and reduce load-carrying clearance. Vehicles that regularly carry heavy loads or tow may need the full travel of the factory setup.

Blocks should never be stacked, and the tallest block practical for safe use is limited by the vehicle and local regulations. Where a larger drop is needed, re-set or replacement springs, or a different suspension approach, will usually be better than a tall block.

Lowering also changes how the vehicle handles under load, and some vehicles are more sensitive to axle wrap than others. Worn leaf spring bushes and shackles will make these effects worse, so inspect them at the same time.

Compliance

Ride height changes are regulated in most regions, so any lowering must keep the vehicle safe and within the standards that apply where it is registered. In the UK and Europe, suspension changes are assessed at the MOT or periodic roadworthiness inspection, and some countries require approval for changes to ride height. Tell your insurer about any change to the vehicle?s suspension or height.

Nolathane Suspension Experience

Nolathane has been making polyurethane suspension bushings since 1974, originally developed to replace brass bushes in hillclimb competition. That background in suspension geometry and axle control is relevant when lowering a leaf-sprung vehicle. The spring eye and shackle bushes play a key role in keeping the axle located once blocks are fitted. Nolathane polyurethane bushes are produced in a range of durometers selected for each application, and their high load-bearing capability and resistance to oil, grease, ozone and weathering help control axle movement and maintain stability after lowering.

Warranty and Support

Nolathane universal lowering blocks are backed by our warranty. Our fitment guarantee means the block you order matches the dimensions shown in the listing, and a 60-day returns window gives you time to confirm the fit. Our local support team can help with block height, U-bolt length and fitting advice, whether you are restoring a classic, lowering a pick-up or completing a custom build.

Shop Universal Lowering Blocks

Nolathane's universal parts range includes lowering blocks to suit custom leaf sprung setups.

Measure your spring width, centre pin and axle perch, compare them with each listing and choose the lowering blocks that suit your vehicle. Orders are sent with fast shipping, so you can achieve the stance you want with a simple, proven leaf spring lowering solution.