do88 DCT Oil Cooler Racing – BMW M3 (E90 / E92 / E93, S65)

OVERVIEW

On track, the E9x M3's DCT gearbox heats its oil quickly and the factory cooler can't keep up, which leads to limp mode and long cool-down laps. The do88 OC-110 replaces it with an 18-row bar-and-plate cooler more than three times the size.

do88 measured gearbox oil at 74 °C after the cooler against 90 °C with the factory part. It drops in on the factory lines and brackets with CNC-machined connections, fits both DCT and manual cars, and can be pre-filled so a full fluid change isn't needed.

SPECS

• 18-row bar-and-plate core
• Core volume: 2,208 cm³ vs 696 cm³ OE — about 217 percent larger
• Active cooling area: 3,456 cm² vs 1,242 cm² OE — about 178 percent larger
• Oil temperature after the cooler: 74 °C vs 90 °C OE (do88 testing)
• Oil volume: 0.65 L vs 0.31 L OE
• CNC-machined oil line connections and brackets
• Replaces OE 17227521376

PARTS INCLUDED

• 1 × do88 OC-110 gearbox oil cooler with CNC-machined connections and brackets

TECH RESOURCES

• Required extras: BMW-approved DCT (or manual gearbox) fluid to pre-fill the cooler and top up.
• Installation instructions (do88): OC-110 M3 DCT oil cooler installation instructions (PDF)
• Installation notes: drop-in on the OE lines and brackets — no modifications. Pre-fill the cooler before fitting, then check the fluid level per BMW procedure.
• Price is for the item only; labor is not included.

PART NUMBER

• OC-110 — do88 DKG / DCT Oil Cooler Racing, BMW M3 E90 / E92

VEHICLE APPLICATIONS