# 1953 Dunbier H3080 Mackay Replacement SSCaliper Piston Suits Hydraulic Caliper # 1956 | Marine Trailer Part

🔧 Product Description

  

Dunbier Stainless Steel Hydraulic-Caliper Piston - Part Number: 1953

  

A replacement stainless-steel piston for the Dunbier 1956 floating hydraulic disc-brake caliper. The corrosion-resistant piston slides through the hydraulic seal and transfers brake-fluid pressure to the inner brake pad, allowing a serviceable AL-KO/Meher-style caliper body to be rebuilt.

  

⚙️ Key Features

  

• Stainless-steel replacement piston

• Designed for Dunbier 1956 hydraulic calipers

• Improved corrosion resistance for marine trailer service

• Restores piston movement and hydraulic sealing

• Allows repair of a sound caliper body

  

📏 Specifications

  

• Component type: Single hydraulic-caliper piston

• Material: Stainless steel

• Application: Dunbier 1956 / Mackay H3010 hydraulic caliper

• Use with a new piston seal and dust boot

  

🔄 Cross Reference & Related Parts

  

• Dunbier: 1953

• Mackay: H3080

• Caliper seal and boot kit: Dunbier 1954 / Mackay H3090

• Slide-pin repair kit: Dunbier 1955 / Mackay H3084

• Complete hydraulic caliper set: Dunbier 1956 / Mackay H3010

  

🚤 Trailer Compatibility & Application

  

• Suits the Dunbier hydraulic caliper used on AL-KO and Meher brake axles

• Confirm piston diameter and caliper casting before installation

• Not suitable for mechanical calipers or unrelated Trojan stainless calipers

  

🔌 Function

  

Converts hydraulic brake-fluid pressure into mechanical pad-clamping movement against the disc rotor.

  

Common signs of wear or replacement:

  

• Piston surface is pitted, scored or rusted

• Brake fluid leaks past the piston seal

• Piston sticks and causes brake drag

• Caliper will not retract after braking

• Uneven pad wear or overheating at one wheel

  

🛠️ Installation & Safety

  

• Brake repair should be completed by a competent trailer-brake technician

• Inspect the caliper bore for corrosion before installing a new piston

• Fit a new O-ring and dust boot; do not reuse damaged seals

• Lubricate only with approved brake-assembly fluid or grease

• Bleed the hydraulic system and verify free wheel rotation after repair

  

📦 Condition

  

• Brand new Dunbier Marine Products trailer component

• Supplied as one stainless-steel caliper piston

• Supplied in original or equivalent packaging

## Details

- **Price:** 84.0 AUD
- **Vendor:** Dunbier
- **Tags:** Dunbier Boat Trailers | Marine Trailer Parts & Accessories

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 84.00 AUD | In stock |

## Images

- 1953 Dunbier H3080 Mackay Replacement SSCaliper Piston Suits Hydraulic Caliper # 1956 | Marine Trailer Part
- 1953 Dunbier H3080 Mackay Replacement SSCaliper Piston Suits Hydraulic Caliper # 1956 | Marine Trailer Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/1953-dunbier-replacement-sscaliper-piston-suits-hyd-caliper-1956-mackay-h3080)
> Updated: 2026-08-05