Diamond T Torque Converter, Ford (1989-05) 5.0/5.4/5.8 E-Series & F-Series (E4OD/4R100) Stage 3 (Triple Disk w/ Billet Cover)

The Diamond T Torque Converter, Ford (1989-05) 5.0/5.4/5.8 E-Series & F-Series (E4OD/4R100) Stage 3 (Triple Disk w/ Billet Cover) – FS89SV8-3 represents the premium level of our Ford gas E4OD/4R100 converter lineup. It shares the same core dimensions as the Stage 1 and Stage 2 units, with a 12-3/4" diameter, 31-spline input, 1.375" pilot (1-1/4" long), milled hub flats and an 11-3/8" 4-stud bolt circle, so it remains a direct-fit option for 5.0L, 5.4L and 5.8L gas E-Series and F-Series platforms from 1989-2005.

Where Stage 1 provides a single-disk upgrade and Stage 2 adds a billet front cover, Stage 3 combines a triple-disk lockup assembly with a billet front cover to deliver the highest lockup clutch surface area and structural rigidity in the series. The triple-disk design dramatically increases lockup holding capacity and distributes load across multiple friction surfaces, while the billet cover reduces flex and helps maintain a consistent apply area under heavy load. Together, these upgrades make FS89SV8-3 ideal for trucks and vans that see serious towing, high combined weights or performance-oriented usage where converter lockup must stay solid and repeatable.

FS89SV8-3 is intended for the same Ford E4OD/4R100 4-stud gas applications with the 5.0L, 5.4L and 5.8L E-Series and F-Series combinations that require this mounting pattern and spline/pilot configuration. As with every Diamond T torque converter, this Stage 3 unit is built with a focus on strength, longevity and real-world performance in demanding service—American Made, Because It Matters.