MAHLE Thermostat – BMW M57N & M57N2 (OE 11517805811)

Description

MAHLE thermostat assembly designed for BMW M57N and M57N2 diesel engines.

Maintains the correct engine operating temperature, helping improve:
✔️ Fuel economy
✔️ Engine performance
✔️ Cabin heating
✔️ DPF efficiency (where fitted)
✔️ Engine longevity

A faulty thermostat is one of the most common causes of low operating temperature on M57 engines.

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Fits BMW Engines

✔️ M57N
✔️ M57N2

Engine Variants

✔️ M57D25TU2
✔️ M57D30TU
✔️ M57D30TU2

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Common Models

• E60 / E61 525d
• E60 / E61 530d
• E60 / E61 535d
• E90 / E91 / E92 325d
• E90 / E91 / E92 330d
• E90 / E92 335d
• E65 / E66 730d
• E70 X5 3.0d / 35d
• E71 X6 35d
• E83 X3 3.0d

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Part Numbers

• MAHLE
• BMW OE: 11517805811

Cross References:

• BEHR / MAHLE: TM 13 97
• BMW: 11 51 7 805 811

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What's Included

✔️ Thermostat assembly
✔️ Housing assembly (depending on manufacturer version)

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Important

❗ Main engine thermostat
❗ Not EGR thermostat
❗ Common failure item on M57 diesel engines
❗ Always check coolant temperature before replacement

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Common Symptoms

• Engine running cold
• Coolant temperature below 88°C
• Poor fuel economy
• Weak cabin heater
• DPF regeneration issues
• Fault code for coolant temperature

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Fitment Summary

✔️ M57N
✔️ M57N2
✔️ BMW 2.5D & 3.0D diesel engines
✔️ OE BMW 11517805811
❌ Not N57
❌ Not M57 (pre-TU)