The turbocharger oil feed line delivers engine oil to lubricate and cool the bearings that support the spinning turbine and compressor shafts. Proper oil feed is essential for turbo reliability, and inadequate oil supply is one of the most common causes of premature turbo failure. ## Turbo Oil Feed Requirements Turbo bearings require a continuous supply of pressurised engine oil. The turbo journal bearings and thrust bearings float on a film of oil, similar to the main and big-end bearings in the engine. Any interruption in oil supply, even briefly, can damage these precision surfaces. The oil feed line runs from the main oil gallery to the turbo bearing housing. Oil pressure at the turbo feed is typically the same as main bearing oil pressure, around 30-50 PSI at idle. High oil pressure ensures adequate flow through the narrow passages in the turbo bearing housing. Factory oil feeds are sized to provide sufficient flow for the standard turbo. When turbos are upgraded or boost levels increased, the factory oil feed may become inadequate. Insufficient oil supply causes bearing overheating and rapid wear. ## Feed Line Sizing and Upgrades Upgraded oil feed lines should be sized to provide adequate flow for the turbo's requirements. Larger diameter lines reduce pressure loss and ensure sufficient oil reaches the turbo, particularly at high engine RPM when oil pressure is higher but the oil passages are relatively smaller restriction points. Quality oil feed lines use braided stainless steel outer braid over a rubber or Teflon inner liner. This construction tolerates high temperatures, resists damage from road debris, and maintains flexibility over the turbo's operating temperature range. The feed line should take the shortest practical route from the oil gallery to the turbo. Long, circuitous routes increase pressure loss and the risk of blockage from debris accumulating in low points. A well-designed oil feed is direct and unsupported along its length. Some performance turbo kits include oil feed line fittings that restrict the flow from the turbo drain side to maintain oil pressure at the bearing housing. This restriction must be correctly sized to match the turbo and engine oil pressure. ## Oil Starvation Causes Oil feed line blockage from debris or sludge accumulation is the most common starvation cause. Particles entering the feed line or building up from degraded oil can block the narrow turbo oil passages, starving the bearings. Oil pump failure or severe oil pressure loss causes immediate oil starvation. Any situation that drops oil pressure below the minimum required by the turbo will cause bearing damage. Regular oil pressure checks help identify pump problems before they cause turbo failure. Oil level low from consumption or leaks reduces the amount of oil available to the turbo feed. Running turbo engines with low oil levels is particularly dangerous because the turbo can consume oil faster than the engine during hard driving. Using incorrect oil viscosity can affect turbo bearing oiling. Low-viscosity oil may not maintain adequate film thickness at high turbo bearing temperatures. Always use the oil grade specified by the manufacturer. ## Frequently Asked Questions **Should the turbo oil feed be restricted?** Factory turbo oil feeds typically include a restrictor fitting to limit flow at high pressure. This prevents excessive oil pressure in the turbo when cold. Upgraded turbos may require different restrictors or no restriction at all. **Can I use any braided line for turbo oil feeds?** Only use lines specifically rated for oil system use at turbo temperatures. Some cheap braided lines use rubber inner tubes that degrade quickly in hot oil. Teflon inner liners are preferred for turbo oil feed applications. **How do I know if my turbo is suffering from oil starvation?** Blue exhaust smoke, excessive oil consumption, turbo lag, and whine are all symptoms of turbo problems that can result from oil starvation. Check oil pressure regularly and investigate any sudden oil consumption increase.

Official Resources: GOV.UK Check Vehicle Tax | GOV.UK Vehicle Tax | DVLA Online | MOT Check

Frequently Asked Questions

Q: How much is car tax (VED) in the UK 2026?
Car tax rates in the UK depend on your vehicle's CO2 emissions and list price. Standard rates start from £190 per year for petrol and diesel cars, with zero-rated VED for EVs. First-year rates vary from £0 to £2,605 depending on emissions. Additional premiums apply for vehicles over £40,000.

Q: How do I check if my car is taxed online?
You can check your vehicle's tax status for free on the Gov.uk website at gov.uk/check-vehicle-tax. You'll need your vehicle's registration number (number plate). You can also check via the Motor Insurance Database to verify road tax and insurance status simultaneously.

Q: Can I get a refund on car tax if I sell my vehicle?
Yes — if you sell or scrap your vehicle, you can claim a refund on any full months of remaining road tax. Contact DVLA with the V11 reminder letter or apply online at gov.uk. Refunds are usually processed within 4-6 weeks.

Q: Is road tax refund available when transferring ownership?
No — road tax does not transfer with the vehicle. When you sell your car, the tax is automatically cancelled and any remaining months are refunded to you by DVLA. The new owner must tax the vehicle immediately. As a buyer, always verify the vehicle's tax status before purchasing. Related: UK Car Turbo Cleaning Guide 2026 | UK Car Turbo Timer Guide 2026 | Car Tax and Road Maintenance UK 2026 | Car Tax and Grit Vehicles UK 2026.

Q: What is the luxury car tax threshold in the UK 2026?
The additional rate for vehicles over £40,000 (list price) adds £410 per year to standard VED rates for years 2-6 of registration. This surcharge brings the annual cost for high-emission vehicles over £40,000 to around £600-690 per year. Pure EVs under £40,000 pay zero VED.