Mosselman Dual Oil Cooler Conversion Kit for BMW 335i E9x (E90/E91/E92) - Setrab 19-Row Aux Cooler - N54/N55 Additional/Twin Oil Cooler Upgrade | 3 Series Performance Engine Cooling for Track & Road

BMW 335i E9x Dual Cooler Conversion by Mosselman with Setrab 19 Row Core

Take control of engine oil temperatures on your turbocharged 3 Series with this Mosselman extension kit. It transforms a factory single cooler layout into a dual setup using a proven Setrab 19 row heat exchanger and high quality hardware. Perfect for fast road, track days and hotter climates, it is a trusted solution for consistent lubrication temperature management on N54 and N55 powered E90, E91 and E92 335i models.

We have installed and used this kit on customer cars and feedback has been outstanding. Owners report dependable oil temp stability, improved resilience against heat soak and greater confidence on spirited drives and circuit sessions. If you are searching for a reliable 335i engine cooling upgrade that integrates cleanly with OEM architecture, this is the one enthusiasts choose.

Key benefits

• Converts single cooler to a dual cooler arrangement for enhanced heat control
• Setrab 19 row auxiliary core for efficient, repeatable cooling performance
• Designed for N54 and N55 engines used on fast road, track days and in warm weather
• Premium brackets and hose kit for a robust, durable installation
• Proven by the community and extensively used on E9x 335i builds

What you get

• 1 x Setrab 19 row cooler
• 1 x Pre-assembled stainless steel left-hand bracket
• 1 x Complete mounting bracket set for the left-side cooler
• 1 x Hose kit

Compatibility

• BMW 3 Series 335i E90 / E91 / E92 with N54
• BMW 3 Series 335i E90 / E91 / E92 with N55

Not sure it fits your car? We can verify before dispatch. For UK vehicles, provide your registration number at checkout. For others, supply the last 7 digits of your VIN.

Installation notes

Not plug and play. Some trimming and adjustments are required to accommodate the extra cooler and bracketry. Additional OEM pieces needed for the left side include:

• Front oil cooler air duct, left
• Wheel arch air duct, left
• Inner wheel arch liner for the auxiliary cooler, left

This kit is recommended for vehicles regularly exposed to higher ambient temperatures or sustained high-load driving where stable oil temperature is essential.

Professional fitting

Prefer a hassle-free install? Book fitting with MJ Modifications in Warwickshire. Request a quote: info@mjmodifications.co.uk.

Part number

OCE9X.N5X.3

Manufactured by

Mosselman

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