Fully Synthetic Engine Oil

Fully synthetic engine oil is engineered rather than simply refined, giving it more consistent protection across a wider temperature range than mineral or semi-synthetic alternatives. At FIXRA, we stock fully synthetic oil from Castrol, Shell, Mobil, Comma, Granville, FUCHS, Liqui Moly, and Valvoline, in every grade commonly specified for UK vehicles.

For most modern cars, a synthetic oil is not an upgrade but a requirement. Extended service intervals, turbocharging, direct injection, and emissions equipment all place demands on the oil that a conventional formulation struggles to meet.

Shop fully synthetic oil by grade

Choose the viscosity your manufacturer specifies:

Shop fully synthetic oil by brand

Our range spans premium and value brands alike, so you can match specification to budget. Browse Castrol oil, Shell oil, Mobil oil, Comma oil, and more.

What is fully synthetic oil?

Fully synthetic oils are built from engineered base stocks with a uniform molecular structure, rather than refined directly from crude. That uniformity delivers better resistance to heat and oxidation, improved cold-start flow, and a longer service life before the oil degrades.

What is the difference between synthetic and fully synthetic oil?

The terms are used loosely across the industry. "Semi-synthetic" or "synthetic blend" products mix synthetic and mineral base oils, offering some of the benefits at a lower price, while fully synthetic contains no conventional mineral base stock. If your handbook specifies fully synthetic, a blend is not an equivalent substitute.

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

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