Genuine BMW N55 Engine Coolant Thermostat OEM 11537601158 Fits 135i, 335i/335xi, X1 35iX, X5 35iX/40iX, X6 35iX/40iX E82 E88 E90 E91 E92 E93 E84 E70 E71

BMW N55 Water Thermostat Assembly – OE Part 11537601158

Keep your turbocharged straight-six running at the correct operating temperature with this factory BMW water thermostat for N55 engines. This original equipment temperature regulator restores stable coolant control, quick warm up and consistent performance on road and spirited drives. Part number 11537601158.

We supply and install this OE assembly regularly on customer cars and on our own builds, and the results speak for themselves: smoother warm up, dependable cooling under load and long-term reliability you can trust from a genuine BMW part.

Why choose this OE temperature regulator

• Original BMW component for the N55 turbo six for precise temperature management
• Direct swap with factory connectors and sealing points, no modifications needed
• Improves heater performance and helps maintain optimal fuel economy
• Stabilises coolant temps during daily use, towing or enthusiastic driving
• Ideal preventative maintenance to avoid overheating and fluctuating gauge readings
• Used by us in-house with consistently excellent customer feedback
• Genuine OE part number: 11537601158

Compatible BMW applications

Designed for N55-powered E-series vehicles. Confirmed fitment includes:

• 1 Series E82 and E88 135i
• 3 Series E90, E91, E92, E93 335i and 335xi
• X1 E84 xDrive 35i
• X5 E70 xDrive 35i and xDrive 40i
• X6 E71 xDrive 35i and xDrive 40i

Typical build ranges: late 2008 through 2014 depending on model and chassis.

Signs your thermostat assembly needs replacement

• Engine takes too long to reach operating temperature
• Temperature swings or creeping temps under load or in traffic
• Heater output is poor despite normal coolant level
• Diagnostic scan reveals thermostat-related faults

Fitment confirmation

We can verify compatibility before dispatch. Provide your UK registration or last 7 of VIN at checkout and we will confirm that 11537601158 is correct for your vehicle.

Professional installation

We recommend expert fitting to protect your engine and ensure correct bleeding of the cooling system. Book with MJ Modifications in Warwickshire for supply and install. Email info@mjmodifications.co.uk for a quote.

Manufacturer and warranty

Manufacturer: BMW

Warranty: Two years for UK customers and one year for international customers when a compatible VIN is provided at checkout.

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