Penrite Gearbox 40 1Ltr

Penrite Classic Gearbox Oil (SAE 40 Equivalent)

Heavy-duty protection for classic gearboxes & overdrives

Penrite Classic Gearbox Oil (SAE 40 Equivalent) is specifically formulated for vintage and classic transmissions where SAE 40 engine oils were originally specified. It provides reliable protection for older gearbox designs while remaining fully compatible with sensitive internal components.

Engineered without modern additive packages that can cause harm, this oil ensures safe, consistent performance in classic driveline systems.

Key Benefits

• Correct for SAE 40 Applications
  Ideal for gearboxes originally requiring SAE 40 or 20W-50 engine oils.
• Safe for Yellow Metals
  Contains no EP (Extreme Pressure) additives, preventing damage to brass, bronze, and phosphor components.
• Overdrive Friendly
  Free from friction modifiers that can cause slipping in systems such as Laycock overdrives.
• Versatile Compatibility
  Suitable for:
  • Straight cut gearboxes
  • Synchromesh transmissions
  • Pre-selector gearboxes
• Consistent Performance Under Load
  Maintains film strength and lubrication in demanding classic driving conditions.

Important Note on Viscosity

Gearbox oils and engine oils are measured differently:

• This oil is rated on the engine oil viscosity scale
• Replaces SAE 40 and 20W-50 engine oils
• Approximate equivalent: 90-weight gearbox oil

Applications

• Classic manual gearboxes
• Vintage transmissions with yellow metal components
• Overdrive units (including Laycock systems)
• Classic and heritage vehicles requiring higher viscosity gearbox oil

Why Choose Penrite Classic Gearbox Oil?

Many modern gear oils contain additives that can damage classic components or affect operation. This formulation avoids those risks, delivering period-correct lubrication with modern reliability, making it ideal for both restored classics and rally-prepared vehicles.