Holden & Chrysler Rear Seal Conversion

Stop the Leaks. Save Your Engine.

Rear main seal leaks are one of the most frustrating and costly problems in classic Holden and Chrysler engines. If you're tired of topping up oil, cleaning your garage floor, or pulling the gearbox (again), you're not alone — and you're not stuck with rope seals.

Why Rope Seals Fail — Again and Again

Many older engines use rope-style rear main seals, which were never built to handle today’s driving conditions. They frequently fail due to:

• Difficult installation – must be packed and trimmed perfectly
• Dry starts or incorrect lube – can cause instant burn or shredding
• Crankshaft imperfections – rope can't conform to wear or grooves
• Outdated materials – crack, dry out, or leak with modern oils
• Bearing cap misalignment – creates sealing gaps

Even well-executed rebuilds are vulnerable — until now.

A Modern Fix: Rear Seal Conversion Kit by Milton Engine Developments

Our Rear Seal Conversion replaces unreliable rope seals with a precision-engineered neoprene lip seal system — for modern, leak-free reliability you can count on.

✅ Key Features:

• CNC-machined components for a precision fit
• Converts rope seal setup to modern neoprene
• Leak-free performance under pressure
• Trusted by Australian engine builders and restoration pros
• Ideal for street, track, or classic applications

What's Included

• Two-piece CNC-machined sealing lips
• Installation instructions

Note: The neoprene rear main seal is available separately and can be added to your order for complete sealing performance.

🧩 Vehicle Compatibility

This rear seal conversion kit is compatible with the following engines and models:

✅ Holden 253 & 308 V8

Passenger Cars:

• HQ, HJ, HX, HZ, WB Kingswood / Premier / Statesman (1971–1984)
• LH, LX, UC Torana V8 (1974–1979)
• VB, VC, VH, VK, VL Commodore V8 (1978–1988)
• Monaro (HQ–HX V8 variants)
• Caprice V8 models

Utility & Vans:

• Holden One Tonner (253 / 308)
• Panel Van (Sandman and variants)

✅ Chrysler 265 Hemi (Inline 6)

• Valiant VH, VJ, VK, CL, CM with 265 Hemi
• Charger E37, E38, E49

Note: This kit suits the Chrysler 265 inline 6-cylinder engine — not LA-series V8s.

🛠️ Fitment Notes

• Engine Types: Holden 253 / 308 V8; Chrysler 265 Hemi (I6)
• Machining Required: Yes – rear main seal area must be machined to suit the CNC lips
• Need help confirming fitment? Contact us and we’ll be happy to assist.

Installation Notes

This kit requires machining to the rear of the block for proper fitment. Machining can be performed by Milton Engine Developments (Adelaide, South Australia) or any reputable machine shop.

Built by Experts, Trusted Nationwide

Developed and supported by Milton Engine Developments, trusted by engine builders and restoration professionals across Australia.

Generally In Stock – Ships from Adelaide

Order today and fix it once — the right way.
📦 Time-sensitive build? Contact us before ordering to confirm current stock levels.

Need a Part Not Listed?

We manufacture and supply a range of specialised components not yet listed online. If you're chasing a rare or custom part, get in touch — we may already have it or can make it for you.