The Eaton Detroit Truetrac is a helical gear-driven limited-slip differential that maximizes available traction while sharpening handling and drivability. It works smoothly and automatically, needs no maintenance, and avoids the on/off behavior of a locker, which makes it a strong choice for street, tow, and trail use.
- Type: Helical gear limited-slip differential
- Axle: Ford 8.8in IFS snap-ring (front)
- Ring gear: 8.8in
- Axle shaft diameter: 1.32in
- Spline count: 31
- Gear ratio: fits all ratios
- Part number: 917A738
Vehicle Applications
- 2009-2025 Ford F-150 (4x4 front axle)
FAQ
What vehicle is the Truetrac 917A738 for?
It fits the Ford 8.8in IFS front axle used in the 2009-2025 Ford F-150 4x4, with a 31-spline count.
Does it work with any gear ratio?
Yes. This Truetrac fits all ring-and-pinion ratios for the 8.8in front axle.
Does the Truetrac need maintenance or a switch?
No. It is fully automatic, needs no maintenance, and has no switch or on/off behavior like a locker.

