6R140 CATEGORY 1 SUNCOAST 650 HP 6R140 TRANSMISSION WITH CONVERTER

SUNCOAST 650+ HORSEPOWER 6R140 TRANSMISSION ASSEMBLY

Transmission contains the following:

Introducing the 6R140

The new 6R140 from Ford is one of the most exciting drivetrains on the market today. It replaced the previous TorqShift unit, the 5R110, which was used in both the 6.0 and 6.4 Ford diesel engines. When Ford released the 6.7L Power Stroke platform, it also introduced the much stronger 6R140 TorqShift transmission.

The Ford 6R140 TorqShift transmission is the most robust transmission Ford has built to date. Designed and manufactured exclusively by Ford Motor Company, it features a one-piece bellhousing that adds significant rigidity and reduces torsional flex.

The transmission includes a deep first gear for towing and load movement, along with double overdrive for improved fuel economy. Gear ratios are as follows: 1st gear 3.974:1, 2nd gear 2.318:1, 3rd gear 1.516:1, 4th gear 1.149:1, 5th gear 0.858:1, and 6th gear 0.674:1.

The patented Lepelletier geartrain simplifies the connection between gear sets and clutches. The 6R140 uses a simple gearset to drive a Ravigneaux gearset, requiring only five clutch packs to achieve six forward gears. Strength is further enhanced with a powder-metal carrier in the compound Ravigneaux planetary gearset, formed from four sinter-brazed components.

The torque converter features a long-travel, high-capacity turbine damper designed to absorb the extreme force produced by the 6.7L Power Stroke. SunCoast has further improved this design with its own line of converters, offering multiple stall options.

The Engineering

When SunCoast evaluated the 6R140, we immediately recognized similarities to the Ford 6R80 and GM 6L80/6L90 platforms. From experience, we knew the 4-5-6 clutch pack, also known as the E-clutch, would be a primary failure point.

Testing different friction materials revealed that higher friction coefficients led to harsher, more aggressive shifts, especially under increased torque. This often resulted in the well-known 3-4 shift squawk.

Rather than reducing friction to mask the issue, SunCoast took a different approach. Through engineering and testing, we developed a solution that improves both performance and drivability, resulting in another patented innovation.

The Patent and the Damper

The factory 6R140 E-clutch hub does not include a damper, as Ford designed the transmission around torque management strategies that reduce power during shifts. Once torque management is removed and power levels increase, failure becomes likely.

SunCoast engineered a new 4-5-6 clutch hub with an integrated damper assembly using sound reduction technology. This eliminates the squawk while restoring smooth, controlled shifts. It also allows for higher performance friction materials, improving durability and reliability.

This patented E-clutch hub damper has proven reliable in applications exceeding 1,000 horsepower and is exclusive to SunCoast.

SunCoast also developed a proprietary 4-5-6 E-clutch power pack using nine custom frictions. This system increases capacity while maintaining clean, consistent shift quality under load.

The Pump Bushing

The factory pump can experience lubrication pressure loss due to bearing seal failure at the converter hub. When the bearing fails, catastrophic damage can occur. This upgraded bearing restores proper operation and reliability.

The Billet Flexplate

SunCoast’s one-piece billet flexplate offers increased strength and durability over factory designs. Precision machining and heat treatment ensure proper concentricity and long-term reliability.

The Deep Pan

The Mag-Hytec 6R140 transmission pan increases fluid capacity and cooling performance. Constructed from A356-T6 aluminum with integrated cooling fins, it provides improved heat dissipation and durability. This pan adds 5.5 quarts over stock and installs as a direct bolt-on replacement.

The Guardian Torque Converter

Ford equipped the 6R140 with sinter-brazed carriers and extended service interval filtration. It also features an integrated live PTO and maintains a lighter overall weight compared to competing platforms.

Captured clutch failure is a common issue in the 6R140 and is difficult to address with stock components alone.