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Size

20L

£14.29

Tax included.

Marine Gear Oil SAE 90 GL-4 (1L)

Name: Westway Marine Gear Oil SAE 90 GL-4 1L - For Yamaha Mercury Honda Suzuki Outboard
Price: 14.29 GBP
Rating: 5.0 (1 reviews)

Professional Grade Lower Unit Lubricant

Keep your marine transmission running smoothly with Westway Marine Gear Oil SAE 90. This high-quality mineral EP (Extreme Pressure) lubricant is specifically engineered for outboard lower units and sterndrives operating in demanding fresh and saltwater environments. Unlike standard automotive oils, this formula is enriched with advanced anti-corrosion and anti-foaming additives to maintain film strength even when moisture is present.

RELIABILITY: Formulated to API GL-4 standards to ensure total safety for yellow metal components (brass/bronze) found in many marine gearboxes.

Key Features

✔ Yellow Metal Safe: API GL-4 rated
✔ Extreme Pressure (EP): Reduces gear wear
✔ Water Emulsification: Protects gears if water enters
✔ Anti-Foaming: Consistent lube at high RPM

Technical Specs

Viscosity:	SAE 90
API Rating:	GL-4
Base:	Mineral
Volume:	1 Litre

Compatibility / Fitment Guide

Make/System	Model/Application	Notes
Yamaha Outboards	2HP - 350HP Models	Lower units requiring SAE 90
Honda Marine	BF2.3 to BF350	Replaces 08251-999-102PRO
Suzuki Marine	DF & DT Series	Suitable for Hypoid gearcases
Mercury/Mariner	Outboards below 75HP	Mineral-spec applications
Tohatsu	All models	Standard service interval

OEM Cross Reference

Honda: 08251-999-102PRO / 08240-999-100

Mercury/Quicksilver: 92-858064K01 / 858059Q01

Suzuki: 99000-22B21-036 / ECSTAR SAE 90

Sierra: 18-9650-2

Questions & Answers

Is this oil safe for brass or bronze components?

Yes. This oil is API GL-4 rated, which means it does not contain the aggressive sulfur-phosphorus additives found in some GL-5 oils that can corrode "yellow metal" synchronizers and bushings.

Can I use this in my Volvo Penta or Mercruiser sterndrive?

Yes, provided your manual specifies a mineral SAE 90 or 80W-90 GL-4 lubricant. For high-performance units (Bravo/DP) that require synthetic gear lube, we recommend checking your manufacturer guidelines.

What happens if water gets into my gearbox?

This marine-specific oil contains advanced emulsifiers that allow it to continue lubricating effectively even with minor water contamination, helping prevent catastrophic gear failure until you can perform a service.

Note: Always check your engine's service manual for exact oil capacity and viscosity requirements. Available at 4boats.co.uk.

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

Free delivery for most items over £150.

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Westway Marine Gear Oil SAE 90 GL-4 1L - For Yamaha Mercury Honda Suzuki Outboard