do88 Transmission Cooler – BMW M2 / M3 / M4 (G87 / G80 / G82, S58)

OVERVIEW

The ZF 8HP behind the S58 is strong, but on track or with a big tune it gets hot, and gearbox oil temperature is often what ends a session. The do88 OC-210 replaces the factory transmission cooler with a dual-pass unit that has 71 percent more core volume and 50 percent more cooling surface, while keeping oil pressure close to stock.

It uses harmonica-style tubes with internal channels to put more of the fluid in contact with the cooling surface, and the dual-pass layout holds the oil in the cooler longer to shed more heat. It keeps the OE-style quick-connect fittings and drops into the factory location with no modifications. Capacity rises from about 6 dl to 8.5 dl, so the fluid level needs to be checked after installation.

SPECS

• Core volume 71 percent larger; cooling surface 50 percent larger than OE
• Dual-pass design with internally channeled harmonica tubes
• Oil capacity 8.5 dl (OE 6 dl), about 42 percent more
• Oil pressure kept close to OE levels
• OEM-style quick-connect inlet and outlet
• Drop-in fit for the ZF 8HP automatic
• Replaces OE 17118095284

PARTS INCLUDED

• do88 performance transmission cooler
• Rock guard
• Foam strip, 2 × zip-ties and 2 × 12 mm silicone caps

TECH RESOURCES

• Required extras: ZF 8HP transmission fluid to the manufacturer specification to top up after installation (the cooler holds about 2.5 dl more than stock), plus a drain tray.
• Installation instructions (do88): OC-210 S58 transmission cooler installation instructions (PDF)
• do88 video (S58 parts overview): do88 BMW G8X S58 upgrades – transmission cooler section (YouTube)
• Installation notes: remove the front wheels, wheel liners and front bumper, then the grille frame, radiator bracket, auxiliary radiator, brake ducts and bumper bar. Pre-fill the do88 cooler and cap it, fit the rock guard and foam strips, swap the coolers quickly to limit fluid loss and confirm both green clips lock.
• After install: check and set the transmission fluid level to the manufacturer's procedure.
• Instructions are shot on an M2; panel removal differs slightly on the M3 and M4.
• Built transmission? See the Pure Drivetrain Solutions ZF 8HP76 rebuilds for the G80 / G82.
• Price is for the item only; labor is not included.

PART NUMBER

• OC-210 — do88 Transmission Cooler, BMW M2 M3 M4 G80 G82 G87 (S58)

VEHICLE APPLICATIONS