DO88 S58 Auxillary Radiator M3 M4

A Common Bottleneck in S58 Cooling Systems

The S58 engine is equipped with a three-radiator setup — one main central radiator and two smaller auxiliary radiators in the corners. These auxiliary radiators are critical for helping maintain coolant temps under sustained load. Unfortunately, the factory units are built with narrow cores and plastic end tanks, which become a weak point on tuned or hard-driven vehicles.

Bigger, Stronger, Cooler

do88’s auxiliary radiators are not just stronger — they’re larger and more efficient. With a 43% increase in core volume and a 13% increase in frontal cooling area, these TIG-welded aluminium upgrades help prevent heat soak and maintain stable coolant temps under pressure.

Key Features

• 43% larger core volume vs. OEM

• Dual-row 48mm thick core

• 13% larger active cooling area

• All-aluminium construction with TIG-welded end tanks

• OE-style quick connect fittings for easy installation

• CNC-machined mounting points

• Compatible with factory rock guards

• Direct-fit for both left and right sides

• Sold individually (one per side)