SAE 90 Gear Oil GL-1 Straight Non Detergent - Yellow Metal Safe - 4Boats

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Size

20L

£14.29

Tax included.

SAE 90 GEAR OIL GL-1

Name: SAE 90 Gear Oil GL-1 Non-Detergent Yellow Metal Safe Classic Marine Gearbox
Price: 14.29 GBP
Rating: 5 (1 reviews)

Straight Non-Detergent Mineral Oil | Yellow Metal Safe

This SAE 90 GL-1 Gear Oil is a high-quality, straight mineral-based lubricant designed specifically for manual transmissions and gearboxes where modern extreme pressure (EP) additives are not suitable. Its non-detergent formula provides essential lubrication without the risk of damaging vintage components.

YELLOW METAL SAFE: Unlike GL-5 oils, this GL-1 formulation contains no active sulfur-phosphorus additives, making it 100% safe for phosphor bronze, brass, and copper bushings or synchronizers common in classic marine and automotive gearboxes.

Key Features

✔ API GL-1 Rated Specification
✔ Straight Mineral (Non-EP) Formula
✔ Resistant to oxidation & thermal degradation
✔ Safe for Copper, Brass, & Bronze components
✔ Excellent rust and corrosion protection

Technical Specs

Viscosity Grade:	SAE 90
API Service:	GL-1
Base Type:	Refined Mineral Oil
Flash Point:	>200°C
Density @ 15°C:	~0.896 kg/L

Compatibility / Fitment Guide

Make/System	Model/Application	Notes
British Seagull	Post-1980 Sealed Gearboxes	Replacement for older SAE 140 requirements in cold climates.
Vintage Tractors	Farmall, Massey, Ford (Classic)	Safe for transmissions with yellow metal bushes.
Manual Transmissions	Spiral Bevel Axles	Where straight mineral GL-1 oil is specified.
Steering Gear	Marine Mechanical Steering	Ideal for older worm gear steering boxes.

OEM Cross Reference

Chevron	Gear Oil GL-1 SAE 90
NAPA	65-205 / NHF 65205
Westway Oils	SAE 90 GL-1 Mineral
British Seagull	SAE 90 (Cold/Post-1980)

Questions & Answers

Is this a genuine original part?

This is a premium quality aftermarket lubricant from Westway Oils, manufactured to meet API GL-1 standards specifically for classic and vintage applications.

How do I know if it is compatible?

Check your owner's manual. If it calls for a "straight mineral oil" or "API GL-1" without EP additives, this is the correct fluid. It is essential for gearboxes containing bronze or brass parts.

Can I use this instead of GL-5 hypoid oil?

No. GL-1 does not have the extreme pressure (EP) additives required for high-load hypoid gears. Conversely, do not use GL-5 in a system requiring GL-1, as the sulfur additives will corrode yellow metal components.

Note: Always verify your equipment's lubrication requirements before use. Distributed by 4boats.co.uk.

For the products under £150 the shipping is £6.99.

Free delivery for most items over £150.

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SAE 90 Gear Oil GL-1 Non-Detergent Yellow Metal Safe Classic Marine Gearbox