Diesel Engine Oil

Modern diesel engines demand high-quality lubricants to keep them running smoothly and efficiently. The right diesel engine oil provides superior protection against wear, helps maintain fuel economy, and extends the life of your vehicle’s engine.

Browse our range of genuine diesel engine oils, or contact Cox Motor Parts for expert advice on selecting the best oil for your vehicle.

Our Range of Diesel Engine Oil

Sale
0W30 Genuine Honda Fully Synthetic C2 Diesel Engine Oil | 4 Litres (08232P99T4LHE)
Original price was: £106.98.Current price is: £57.99.
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5W30 Genuine Honda Fully Synthetic Engine Oil | 1 Litre (08232P99C1LHE)
Original price was: £22.38.Current price is: £13.43.
Save 40% VIEW PART
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5W30 Genuine Honda Fully Synthetic Engine Oil | 4 Litres (08232P99C4LHE)
Original price was: £86.76.Current price is: £47.88.
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Out of Stock

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Castrol Edge Professional H C2 0W30 Fully Synthetic Engine Oil 1 Litre
Original price was: £19.09.Current price is: £13.99.
Save 27% VIEW PART
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Castrol Magnatec 0W30 Stop-Start C2 Fully Synthetic Engine Oil 4 Litres
Original price was: £52.27.Current price is: £31.99.
Save 39% VIEW PART
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Genuine Honda Green Diesel Oil (Earth Dreams Technology) 1.6 i-DTEC Diesel Engine Oil 1 Litre (08232P99D1LPRO)
Original price was: £30.04.Current price is: £16.99.
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Genuine Honda Green Earth Dreams Technology 1.6 i-DTEC Diesel Engine Oil 4 Litres (08232P99D4LHE)
Original price was: £115.49.Current price is: £59.99.
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Mobil 1 ESP 0W30 Fully Synthetic Engine Oil 1 Litre
Original price was: £19.09.Current price is: £10.59.
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Mobil 1 ESP 0W30 Fully Synthetic Engine Oil 5 Litres
Original price was: £81.72.Current price is: £47.58.
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Mobil 1 ESP 5W30 Fully Synthetic Engine Oil 1 Litre
Original price was: £19.62.Current price is: £13.62.
Save 31% VIEW PART
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Mobil 1 ESP 5W30 Fully Synthetic Engine Oil 5 Litres (157295)
Original price was: £81.72.Current price is: £49.99.
Save 39% VIEW PART

Fully Synthetic Engine Oil for Diesel Engines

Using the correct car oil for diesel engines doesn’t just protect your engine – it can improve fuel economy, reduce emissions, and extend the time between services, saving you money and minimising your environmental impact. Whether you drive a modern diesel with a particulate filter or an older model, we have the right oil to meet your vehicle’s specifications.

While diesel engines deliver excellent fuel economy and torque, they generate significantly more soot during combustion compared to petrol engines. This soot and other combustion byproducts make finding the right diesel oil important for maintaining performance.

The ideal diesel oil formulation contains advanced additives that suspend and neutralise these contaminants, preventing them from causing wear or building up as harmful deposits. Quality diesel engine oils also withstand the higher operating temperatures these engines typically reach, maintaining proper viscosity and protection from wear and corrosion even under demanding conditions.

At Cox Motor Parts, we’ve built our expertise through years of experience supplying engine oils for diesel and petrol vehicles, so we understand what your car needs to perform optimally. Our carefully curated selection includes premium, fully synthetic oils and lubricants from trusted brands like Castrol, Mobil, and Honda, all formulated specifically to keep your diesel engine running smoothly, lasting longer, and performing at its best.

How to Choose the Right Diesel Engine Oil for Your Vehicle

We make finding the correct engine oil for diesel engines simple:

Determine Your Oil Specification

Different diesel engines require specific oil formulations. Your vehicle handbook typically expresses the recommended specification as a viscosity grade (5W-30) and quality standard (ACEA C3). Using the manufacturer-recommended oil guarantees your engine receives the protection it needs.

Select Your Oil

Once you’ve found the oil that matches your vehicle with the correct specifications, our team will verify your selection before dispatch, giving you complete confidence in your purchase.

Change Your Diesel Engine Oil

Make sure your engine is cool before starting. Drain the old oil completely, replace the oil filter, and add the new oil to the correct level. For the best results, follow your vehicle manufacturer’s recommended oil change intervals and procedures.

Diesel Motor Oil FAQs

Due to their higher operating temperatures and compression ratios, diesel engines have different lubrication needs than gasoline engines. The “best” diesel engine oil depends on your vehicle, driving conditions, and manufacturer recommendations. If you’re simply trying to find the right engine oil for your Honda, we’ve got you covered with genuine Honda products. However, if you’re looking for the best overall, we offer premium options from trusted brands. Based on customer feedback and performance, good oils for diesel engine oils include:

The right diesel oil is a small investment that pays off in longer engine life and better overall vehicle performance:

Extends your engine’s life by protecting moving parts from soot and contaminants
Improves fuel efficiency, helping you get more miles per tank
Reduces the frequency of oil changes with better-performing formulations
Makes sure your engine delivers optimal performance and power
Provides specialised protection against the higher temperatures and pressures in diesel engines

Diesel motor oil should work perfectly fine in either type of engine. You just need to make sure that it’s still the right oil for your needs. To check this, you’ll need to work out whether the diesel oil:

Matches the viscosity requirements
Offers protection against your driving conditions

As fully synthetic diesel oils are designed for higher temperatures, they can generally be used to cover the less extreme temperatures standard motor oil is designed for. We would not recommend you use petrol oil in a diesel engine, though.

You can mix your diesel and regular motor oil. In the short term, this shouldn’t be much of a problem as each is a synthetic oil created in similar ways, which means that mixing the oils won’t create any negative by-products. But it’s not recommended to mix these oils over a long period. You won’t gain any major benefits and could lose out on the optimal performance the original oil was engineered to offer. This would be a short-term solution rather than a long-term fix.

You can use 5W30 oil in many diesel engines, but only if it meets your vehicle’s specific requirements. The 5W30 viscosity grade is commonly recommended for both petrol and diesel engines, but diesel engines need oils with additional additives and higher performance specifications. Always check that the 5W30 oil you’re considering is explicitly labelled for diesel use and meets your manufacturer’s recommended standards (such as ACEA C3 or API CK-4). Using the wrong oil can reduce engine protection and potentially affect your warranty.

Fresh diesel engine oil typically has an amber or honey-coloured appearance, similar to petrol engine oil. However, diesel oil darkens much more quickly during use due to the higher soot content produced by diesel engines. This darkening is normal and doesn’t necessarily mean it needs changi

Diesel Engine Oil

Our Range of Diesel Engine Oil

0W30 Genuine Honda Fully Synthetic C2 Diesel Engine Oil | 4 Litres (08232P99T4LHE)

5W30 Genuine Honda Fully Synthetic Engine Oil | 1 Litre (08232P99C1LHE)

5W30 Genuine Honda Fully Synthetic Engine Oil | 4 Litres (08232P99C4LHE)

Castrol Edge Professional H C2 0W30 Fully Synthetic Engine Oil 1 Litre

Castrol Magnatec 0W30 Stop-Start C2 Fully Synthetic Engine Oil 4 Litres

Genuine Honda Green Diesel Oil (Earth Dreams Technology) 1.6 i-DTEC Diesel Engine Oil 1 Litre (08232P99D1LPRO)

Genuine Honda Green Earth Dreams Technology 1.6 i-DTEC Diesel Engine Oil 4 Litres (08232P99D4LHE)

Mobil 1 ESP 0W30 Fully Synthetic Engine Oil 1 Litre

Mobil 1 ESP 0W30 Fully Synthetic Engine Oil 5 Litres

Mobil 1 ESP 5W30 Fully Synthetic Engine Oil 1 Litre

Mobil 1 ESP 5W30 Fully Synthetic Engine Oil 5 Litres (157295)