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15W-40 Engine Oil

15W-40 Engine Oil

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15W-40 engine oil is a heavier multigrade lubricant most often specified for diesel engines, commercial vehicles, and older petrol cars. At FIXRA, we stock 15W-40 oil designed to maintain a strong protective film under sustained load and higher temperatures, where a thinner modern grade would not be suitable.

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Comma X-Flow Type MF 15W-40 5L
Comma
Comma X-Flow Mineral Engine Oil Type MF 15W-40 5L

Item number: XFMF5L

£28.19
£28.19
£28.19
Shell Helix Engine Oil HX5 15W-40 1L
Shell
Shell Helix Engine Oil HX5 15W-40 1L

Item number: 550046277

£10.79
£10.79
£10.79
Shell Helix Engine Oil HX5 15W-40 5L
Shell
Shell Helix Engine Oil HX5 15W-40 5L

Item number: 550039863

£48.19
£48.19
£48.19
Castrol GTX 15W-40 A3/B3 Engine Oil 1L
Castrol
Castrol GTX 15W-40 A3/B3 Engine Oil 1L

Item number: 15F627

£8.29
£8.29
£8.29
Castrol GTX 15W-40 A3/B3 Engine Oil 4L
Castrol
Castrol GTX 15W-40 A3/B3 Engine Oil 4L

Item number: 15F628

£32.59
£32.59
£32.59
Granville Hypalube Mineral Plus Engine Oil 15W-40 5L
Granville
Granville Hypalube Mineral Plus Engine Oil 15W-40 5L

Item number: 0180

£25.49
£25.49
£25.49

Because it is thicker at operating temperature than grades such as 5W-30, 15W-40 oil remains a service staple for hard-working engines, higher-mileage vehicles and applications that cover long hours rather than short journeys.

This grade of engine oil is widely used in light commercials, vans, tractors, and older diesel engines, where its higher operating viscosity helps maintain oil pressure and reduce consumption. 

Our range covers mineral and semi-synthetic formulations to suit both everyday servicing and heavier-duty use. If your vehicle takes a lighter grade, our 10W-40 engine oil collection is the usual next step. Always check your handbook or use our registration lookup before ordering.

Shop 15W-40 engine oil at FIXRA with free delivery on orders over £20 and next-day delivery options available, plus a 60-day returns policy and Click & Collect at your nearest parcel shop.