CSF Transmission Cooler - BMW M2/M3/M4 G8x

In stock form the G8X is an impressive machine, but its tuning potential is where the magic really happens. However, whenever you start pushing power on a car, you need to make sure the cooling system can keep up. CSF’s new G8X M3/M4 Transmission Oil Cooler for the ZF8 Automatic should definitely be at the top of your list.

CSF worked closely with development partner, sponsored race team, and premier local CSF Dealer Studio RSR as well as Time Attack Teams such as Art of Attack and Velocity Performance on the ZF8 Automatic Transmission Oil Cooler. Their insight, experience, and testing feedback provided invaluable insight into designing the best cooler possible.

Design, Development, and Testing

While the OEM Transmission Cooler is adequate for the G8X in stock form, it starts to come up a bit short on modified/tuned vehicles. Specifically ones that see heavy track/competition use. Transmission oil temperatures have a major impact on the shifting performance of your automatic transmission. If the fluid passes optimal temperatures you will start to see some delays in shifting. Sluggish shifting can be quite frustrating, but the real concern is the damage that can be done to the transmission when temperatures get too high. There are often cases where drivers don’t notice the change in shifting performance due to the gradual onset, but the damage is still being done slowly on a very expensive and important component.

Dual-Core Advantage

By changing from the OEM single core design to a dual core, CSF was able to increase the overall volume by 194%. This design offers a drastic improvement in heat dissipation and increases the fluid capacity of the coolers by ~94%. Utilizing CSF’s AC Condenser Technology, a 1-Row Super-High Pressure 16mm 9-Channel Microtube design optimizes oil flow and offers maximum surface area contact. These features combine to offer the best possible heat dissipation from the system.

Rock Guard

CSF knows the kind of punishment the front of a car can take on or off the track. The wrong bit of debris flying through the front grille can quickly punch a hole in a cooler. Because the Transmission cooler sits at the very front of the center cooling stack, it is quite vulnerable to damage. In addition, “open face” race style grilles have become quite popular on the G8X. These grilles can add to the risk of debris passing through.

The factory grille is the only form of protection for the OEM transmission cooler. However, this still isn’t the level of protection many race teams and enthusiasts are comfortable with. To address this concern, CSF has incorporated a replaceable rock guard to keep your cooler safe and your G8X running strong in the event of debris making it through the front grille.

OEM vs CSF

The CSF Transmission Cooler features a unique dual pass design. You can see in the diagram below how the OEM Cooler’s single pass design works by flowing across the core and back through a feed pipe. While perfectly functional, this gives some extra height to work with if you can eliminate the feed pipe.

Testing & Feedback

Studio RSR tested the new Transmission Oil Cooler on their G80 M3 Time Attack car during several events. The team competes in Global Time Attack events year round. In addition, their G80 M3 spends many weekends at the track to test new setups and modifications. Their experience and feedback on the real world performance of CSF products has been key in the development of all the new G8X cooling products.

There was a noticeable reduction in transmission temperatures on track. The combination of the transmission temps being in check and the new rock guard gave us extra peace of mind while on both the track and road.

"There was a noticeable reduction in transmission temperatures on track. The combination of the transmission temps being in check and the new rock guard gave us extra peace of mind while on both the track and road."

-Studio RSR