GLC63 M177 Transmission Split Cooling

Product Details

• -10AN fittings and lines for excellent flow
• CNC billet aluminum end tanks
• Bar and Plate style for increased strength and capacity
• Core size is 575mm x 140mm x 42mm

Kit Includes

• 1 x Bar and Plate Oil Cooler
• 1 x aluminum fluid divorcer with -10AN fittings
• 2 x -10AN braided fluid lines
• 2 x Cooler mounting brackets and hardware
• 2 x Horn relocation brackets with mounting hardware
  

Product Background

On M177 Mercedes vehicles, the same coolant is used to cool down the water to air intercoolers as well as the transmission. Even at stock power levels, this is not sufficient as the system quickly heat soaks and you are robbed of power due to high intake air temperatures which are in part driven by the transmission. Your transmission also has to fight for the same cooling capacity and generally runs hotter than desired, especially after spirited driving

Our design solves these OEM shortcomings by completely divorcing your transmission oil from the intercooler fluid circuit. Our system uses a bar and plate oil cooler that mounts to the front crash bar to directly cool your transmission without having a fluid oil/coolant exchanger. Using our custom billet fluid divorcer we are now able to reroute the transmission oil to its dedicated radiator resulting in colder transmission and intake temperatures.

Measured Results · Tested on a 2019 E63 S

+22°C

Stock peak IAT rise over ambient, pull 3

+14°C

With split cooling, pull 3

−36%

Average peak IAT rise, three pulls

Method: Same M177 cooling layout and the same split cooling system as this GLC63 kit. 10-min highway warm-up, then three consecutive pulls with no cooldown. Ambient 30°C stock / 31°C split. Customer-submitted data, October 2026. Read the full test →

Installation

Installation Instructions (PDF)