Name: 15w40 Semi-Synthetic Engine Oil Petrol / Diesel
Brand: Westway Oils
SKU: 4067-5
Price: 32.99 GBP
Availability: InStock

15w40 Semi-Synthetic Engine Oil Petrol / Diesel - 4Boats

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Our stock levels are dynamic and can change frequently. If a product appears to be in stock, it may have already sold out. Please contact us if you have any questions about availability. Thank you for your understanding.

Size

20L

25L

£32.99

Tax included.

15W40 SEMI-SYNTHETIC ENGINE OIL

Premium Quality Mixed-Fleet Marine Lubricant

This high-performance 15W-40 Semi-Synthetic Engine Oil is a new-generation multi-grade lubricant manufactured from carefully selected base oils and advanced additive technology. Designed for ultimate versatility, it is an ideal mixed-fleet lubricant suitable for both petrol and diesel engines, providing superior protection over standard mineral-based oils.

RELIABILITY: Formulated with dispersant and detergent additives to maintain engine cleanliness, reduce deposits in turbochargers, and provide excellent high-temperature stability.

Key Features

✔ Semi-Synthetic high-shear formulation
✔ Improved fuel efficiency & emissions
✔ Excellent thermal & oxidation stability
✔ Stay-in-grade multi-grade performance

Technical Specs

Viscosity	15W-40
API Rating	SL / CH-4
ACEA Rating	A3, B3, B4, E2
Base Oil	Semi-Synthetic

Compatibility / Fitment Guide

Engine Type	Application	Notes
Marine Diesel/Petrol	Inboard Engines	Perfect for units requiring 15W40 SL/CH-4 grade.
Automotive	Mixed Fleets / Vans	Excellent for high-mileage mixed petrol/diesel fleets.
Agricultural	Tractors / Gen-Sets	Heavy-duty cycle protection for stationary & mobile units.
Turbocharged	Diesel & Petrol	Specific detergents combat turbocharger deposits.

OEM Performance Equivalent

Mercedes-Benz	MB 228.1, MB 229.1
MAN	MAN 271
Volvo	VDS
Volkswagen	VW 501.01, 505.00

Questions & Answers

Is this oil suitable for turbocharged engines?

Yes, the specific detergent additives in this semi-synthetic formula are engineered to reduce unwanted deposits in turbochargers and on pistons, ensuring efficient operation under pressure.

How do I know if it is compatible?

Check your engine owner's manual for the required viscosity (15W-40) and API/ACEA specifications. This oil is suitable for any engine requiring an API SL or CH-4 lubricant.

What are the benefits of Semi-Synthetic over Mineral?

Semi-synthetic oils offer improved thermal stability, better cold-start protection, and reduced oil consumption compared to standard mineral oils, extending the life of critical engine components.

Note: Please verify your original equipment manufacturer requirements against the specifications above before purchasing. 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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15w40 Semi-Synthetic Engine Oil Petrol / Diesel