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The HD Holden (1965–1966) often gets overshadowed by what came before and after it, but underneath, it represents a meaningful step forward in Holden’s mid-60s suspension tuning philosophy. It sits between the earlier EH-era simplicity and the more refined HR update, carrying forward the same basic layout but with subtle improvements in ride quality, steering feel, and chassis control.
This was still very much a car designed for Australian conditions — rough roads, long distances, and heavy use — but by the HD era, Holden engineers were clearly paying more attention to refinement. The result is a familiar driving experience, but with a slightly more composed edge compared to earlier models.
HD Suspension Setup
The HD continues with Holden’s proven full-size layout: independent front suspension and a live rear axle. Simple, durable, and easy to maintain — exactly what buyers expected at the time.
Front Suspension
Independent unequal-length control arm front suspension
Coil springs mounted to upper control arm geometry
Hydraulic shock absorbers
Front stabiliser (sway) bar
Steering box mounted to front crossmember
The HD front end is tuned heavily toward comfort, but with slightly improved control over secondary movement compared to EH models.
The biggest improvement comes from damping calibration. Earlier cars tended to feel a little soft and slow to settle after bumps, while the HD introduces a more controlled rebound cycle. It still rides softly, but it doesn’t feel quite as floaty over uneven surfaces.
Rear Suspension
Live rear axle with semi-elliptic leaf springs
Hydraulic shock absorbers mounted to axle
Heavy-duty differential housing
Optional rear sway bar depending on variant
The rear suspension remains straightforward and rugged. Leaf springs provide load-carrying ability and durability, but also introduce some axle movement under cornering load.
HD refinement work improves rear damping slightly, helping reduce oscillation over longer undulations and improving stability on open roads.
Steering System
The HD Holden uses a recirculating ball steering system, consistent with other Holden models of the era.
Power Steering System (where fitted)
Recirculating ball steering box
Hydraulic power assist (optional equipment)
Pitman arm and idler arm linkage system
Drag link steering geometry
Engine-driven power steering pump
Steering is light and easy at low speeds, particularly with power assist. At higher speeds, it remains stable but not especially precise.
The inherent design includes some free play due to the multi-link system, meaning steering response is slower than modern rack-and-pinion setups. However, this was considered normal for the class at the time.
Suspension Changes From EH Holden
The HD is best understood as a refinement rather than a redesign.
Key improvements included:
revised damper valving for improved rebound control
slightly improved spring calibration for ride balance
upgraded bush compounds for reduced compliance movement
improved straight-line stability at highway speeds
reduced front-end bounce after larger bumps
better durability under sustained load conditions
These changes give the HD a slightly more confident feel, particularly on longer highway runs where stability matters more than outright softness.
Common HD Suspension Issues
Like most classics of this era, time is the biggest factor affecting suspension performance.
Front Control Arm Bush Wear
Rubber deterioration is extremely common.
Symptoms:
wandering steering at speed
knocking over bumps or braking
uneven tyre wear
vague steering response
Ball Joint Wear
Front suspension joints carry significant load and wear over time.
Symptoms:
clunking over bumps
looseness in steering feel
instability under braking
Tie Rod End Wear
Essential for steering accuracy and alignment.
Symptoms:
excessive steering play
uneven tyre wear
poor straight-line tracking
Steering Linkage Wear
Multiple joints in the steering system can develop play.
Symptoms:
slack steering feel
wandering at highway speeds
inconsistent steering response
Leaf Spring Fatigue
Rear leaf packs naturally lose rate over decades.
Symptoms:
rear sagging
reduced ride height
harsh bottoming under load
instability when carrying passengers or cargo
HD Suspension & Steering Components (Service Overview)
Exact OEM part numbers vary depending on body style (sedan, wagon, ute), engine configuration (inline-six variants), and trim level (Standard, Special, Premier derivatives). However, the HD platform generally includes the following service components:
Front Steering Components
Steering box assembly (recirculating ball type)
Pitman arm
Idler arm
Drag link assembly
Inner and outer tie rod ends
Steering column coupling components
Power steering pump and hydraulic lines (if fitted)
Front Suspension Components
Upper and lower control arms
Front coil springs (rate-specific per engine and trim)
Front shock absorbers
Front sway bar and links
Ball joints (upper and lower depending on configuration)
Control arm bushes
Rear Suspension Components
Multi-leaf rear spring packs
Rear shock absorbers
Rear axle housing
U-bolts and spring mounts
Optional rear sway bar (model dependent)
Steering System Ancillaries
Hydraulic steering pump (if equipped)
Reservoir and return lines
Steering box mounting bushes
Steering linkage joints and seals
As with most vehicles of this age, it is extremely common for multiple components to be worn simultaneously. A full suspension refresh typically delivers a far greater improvement than replacing individual parts in isolation.
Best Suspension Upgrades for HD Holden
The HD responds well to modern suspension improvements while still retaining its original character when done tastefully.
Popular upgrades include:
modern shock absorbers with improved damping control
upgraded front control arm bushes (including polyurethane options)
heavy-duty sway bars for reduced body roll
refreshed steering linkage components for tighter response
leaf spring reconditioning or replacement packs
upgraded ball joints and tie rod ends for improved accuracy
These upgrades deliver:
improved highway stability
reduced body roll in corners
better steering response and feel
improved tyre wear control
and a more composed overall driving experience
It’s still very much a comfort-first design, built around simplicity and durability, but the HD adds a layer of polish that makes it more pleasant to live with on longer drives.
Previous: EH Holden Suspension and Steering
Next: HR Holden Suspension and Steering