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Change Car Turbo

Very technical 4h00–30h00 ~400–3000£
Estimated time 4h00–30h00
Estimated labour cost ~400–3000£
Difficulty Very technical
Vehicles
X4 2014-2018 10
  • M40i Petrol (N55B30A)
  • xDrive 20d Diesel (B47D20A)
  • xDrive 20d M Performance Diesel (B47D20A)
  • xDrive 20i Petrol (N20B20A)
  • xDrive 28i Petrol (N20B20A)
  • xDrive 30d Diesel (N57D30A)
  • xDrive 30d Diesel (N57D30A)
  • xDrive 30d M Performance Diesel (N57D30A)
  • xDrive 35d Diesel (N57D30B)
  • xDrive 35i Petrol (N55B30A)
X4 2018-2025 16
  • M Competition Petrol (S58B30A)
  • M Petrol (S58B30A)
  • M40d mHev 48V (MHEV),Diesel (B57D30B+JA1)
  • M40i mHEV 48V (MHEV),Petrol (B58B30B)
  • M40i Petrol (B58B30A)
  • M40i Petrol (B58B30B)
  • xDrive 20d Bi-Turbo Diesel (B47D20B)
  • xDrive 20d Bi-Turbo Diesel (B47D20B)
  • xDrive 20d Bi-Turbo mHev 48V (MHEV),Diesel (B47D20B+JA1)
  • xDrive 20d Bi-Turbo mHev 48V (MHEV),Diesel (B47D20B+JA1)
  • xDrive 20d Diesel (B47D20A)
  • xDrive 20i Petrol (B48B20A)
  • xDrive 25d Diesel (B47D20B)
  • xDrive 30d Diesel (B57D30A)
  • xDrive 30d mHev 48V (MHEV),Diesel (B57D30B+JA1)
  • xDrive 30i Petrol (B48B20B)

What is the role of the BMW X4 turbo?

The turbocharger increases engine power by compressing the intake air, allowing more air (and therefore more fuel) into the combustion chambers. It is driven by exhaust gases spinning a turbine at speeds up to 250,000 rpm. The compressed intake air passes through an intercooler to reduce its temperature before entering the engine.

What are the symptoms of a failing BMW X4 turbo?

Common symptoms include: loss of engine power or boost, excessive exhaust smoke (blue/white for oil burning, black for over-fuelling), whining or whistling noise from the turbo area, engine warning light or turbo fault codes, oil leaks at the turbo housing, increased oil consumption.

What causes BMW X4 turbo failure?

The main causes are: oil starvation (blocked or restricted oil feed lines, low oil level, poor oil quality), foreign object ingestion, excessive exhaust temperature, worn bearings due to high mileage, and contaminated oil. Always investigate and fix the root cause before fitting a replacement turbo.

Can a BMW X4 turbo be reconditioned?

Yes, turbo reconditioning is a common and cost-effective alternative to buying new. A reputable service will disassemble, inspect, replace worn parts, rebalance, and test the unit. Expect to pay 30–60% of the new price.

Is it difficult to change a BMW X4 turbo?

Difficulty level 5/5: very technical. The turbo is connected to both the intake and exhaust systems, requiring numerous disassembly steps. Approximately 5 hours on average for a professional mechanic. Key precautions after fitting: change the engine oil and filter, prime the turbo with oil before starting, allow the turbo to cool down after hard driving by idling for 30 seconds before switching off.

2 models covered

Model Year Range Engines covered Fuel
X4 2014-2018 2014-2018 M40i Petrol (N55B30A), xDrive 20d Diesel (B47D20A), xDrive 20d M Performance Diesel (B47D20A), xDrive 20i Petrol (N20B20A), xDrive 28i Petrol (N20B20A), xDrive 30d Diesel (N57D30A), xDrive 30d Diesel (N57D30A), xDrive 30d M Performance Diesel (N57D30A), xDrive 35d Diesel (N57D30… Diesel, Petrol
X4 2018-2025 2018-2025 M Competition Petrol (S58B30A), M Petrol (S58B30A), M40d Diesel (B57D30B), M40d mHev 48V (MHEV),Diesel (B57D30B+JA1), M40i mHEV 48V (MHEV),Petrol (B58B30B), M40i Petrol (B58B30A), M40i Petrol (B58B30B), xDrive 20d Bi-Turbo Diesel (B47D20B), xDrive 20d Bi-Turbo Diesel (B47D20B), … 48V (MHEV), Diesel, Petrol