Mosselman Single-to-Twin Oil Cooler Extension Kit – BMW E82/E88 135i & 1M (N54/N55) – Setrab 19-Row – OCE8X.N5X.3

Mosselman Dual Oil Cooler Conversion for BMW 1 Series E8x

Part number: OCE8X.N5X.3

Unlock dependable oil temperature control on your E8x with this Mosselman dual-cooler extension. Designed for the 1 Series coupe and cabriolet, including 135i and 1M models with the twin-turbo straight-six, this package adds a second high-efficiency cooler on the opposite side to the factory unit. The result is greater cooling headroom, stable temps during hard driving, and peace of mind on hot days and track sessions.

Built around a genuine Setrab nineteen-row core and robust Mosselman brackets and hoses, this conversion is a proven upgrade for enthusiasts who want a durable, motorsport-grade oil cooling solution. We have run this kit on our own cars and customer builds and feedback has been consistently positive.

Why enthusiasts choose this kit

• Dual oil radiator layout for increased thermal capacity and balanced cooling
• Setrab heat exchanger known for efficiency, flow and reliability
• Excellent for spirited road use and track days in high ambient temperatures
• Engineered hardware for a neat, secure and long-lasting installation
• Ideal supporting mod for tuned N54 and N55 cars that see extended load

Search intent covered: BMW 1 Series oil radiator upgrade, E8x dual oil cooler conversion, 135i oil temperature solution, 1M oil cooling kit, N54 performance cooling, N55 oil cooling upgrade, E82 E88 oil cooler lines and brackets, Setrab oil cooler pack, track day oil cooler, heat management for tuned BMWs.

What you receive

• 1 x Setrab 19 row oil cooler
• 1 x Pre-assembled stainless bracket for the left side
• 1 x Complete mounting bracket set for the left cooler
• 1 x Hose kit specific to the E8x twin cooler conversion

Vehicle suitability

• BMW 1 Series 135i E82 E88 with N54
• BMW 1 Series 135i E82 E88 with N55
• BMW 1 Series 1M E82 with N54

Common searches: E8X oil cooler upgrade, BMW 135i dual cooler kit, 1M auxiliary oil cooler, E82 E88 performance cooling, N54 oil radiator, N55 track cooling, Setrab cooler for BMW, twin cooler add-on, oil temp stability, overheating prevention for fast road and circuit use.

Installation notes

This is not a simple plug-in. Some trimming and additional OEM ducting are required to position the extra cooler and ensure proper airflow.

Additional BMW parts typically required:

• Front air duct for the left-hand cooler
• Left wheel arch air duct
• Inner wheel arch liner for the auxiliary cooler on the left

1M specific note: The 1M has an auxiliary water radiator on the left, which occupies the location for the second oil cooler. To run a twin setup, that water cooler must be removed and a larger main radiator may be required. Allow extra labour time for 1M fitment.

Professional fitting

Want it done properly first time? Book installation with MJ Modifications in Warwickshire. Request a fitting quote at info@mjmodifications.co.uk.

Compatibility check before dispatch

We verify suitability before shipping. Please add your UK registration or the last 7 of your VIN at checkout so we can confirm this Mosselman dual cooler extension is correct for your vehicle.

Built for hot weather and hard use

If you drive your E8x hard, this twin-cooler conversion delivers consistent oil temperature control and confidence lap after lap. A smart addition for performance-focused builds where reliability matters.