A Tremec 3160 six-speed directs power from the GT350’s 5.2-liter engine
By Steve Turner
Photos courtesy of Ford Motor Company
We know a special engine powers the Shelby GT350 and GT350R. The 5.2-liter V-8 sports a game-changing flat-plane crankshaft, which beefs up its midrange torque and extends the engine’s rev range. The result is an impressive output of 526-horsepower and 429 lb-ft of torque, which adds up to over 100 horsepower per liter.
To make the most of that engine, you need a transmission that is strong enough for the task, but doesn’t weigh things down. The gearbox that answered the call for this high-revving combo is a GT350-specific version of Tremec’s 3160 six-speed manual transmission.
“Any transmission backing this engine requires a certain amount of high-power, high-rpm capability,” Jeff Albers, Ford powertrain engineering supervisor, said.
The 3160 balances durability and weight in a modern package. It features a unique clutch housing and a shortened rear housing featuring strategically placed ribs for strength. Its 3.2-inch center-to-center distance is said to allow for a high torque capacity inside that compact package. Of course, being small and stiff helps ward off those three words manufacturers dread—noise, vibration, and harshness.
Inside, it features a gun-drilled main gear shaft, which reduces weight. Its gears are power honed after heat-treating to reduce weight and improve smoothness. And, its synchronizers are built from a blend of carbon and bronze to offer improved shift feel and heat resistance.
In the case of the GT350, heat was an area that engineers focused on. If you plan to take yours to the racetrack, you should consider the Track Package or the R-model, as they both feature an air-to-oil transmission cooler fed by a gerotor pump in the transmission. In applications without the cooler, the transmission features neither the pump nor the plumbing needed to support the cooler, which is mounted right behind the front fascia and fed ambient air.
Whether it is fitted with an external cooler or not, the Tremec 3160 features the following ratios: First Gear: 3.253:1, Second Gear: 2.233:1, Third Gear: 1.611:1, Fourth Gear: 1.243:1, Fifth Gear: 1.00:1, and Sixth Gear: 0.629:1. From what we could tell in the passenger seat, this gearing combined with the 5.2-liter’s elastic powerband proves to be a happy combination on the road course.
Clearly, Ford Performance engineers worked with Tremec to craft a gearbox that follows suit with the rest of the GT350 program, focusing on maximum performance in the lightest possible package.