Section 10: Drivetrain¶

High (8)

• Re-spec 8HP70 → NP241OR adapter path (case changed from JK NV241 to TJ Rubicon Rock-Trac) (#313) — The transfer case selection changed from the JK NV241 GenII Command-Trac (2.72:1) to the TJ/LJ Rubicon NP241OR Rock-Trac (4:1) (owner decision, 2026-09-18 — deeper low range). All the adapter research on the transfer-case page was done against the JK case and does not carry over automatically.
• iBooster pedal ratio verification against 1.25" booster stroke (#301) — Verify the brake pedal ratio (approximately 4:1 per owner notes, 03-06 TJ/LJ auto pedal) against the Bosch Gen 2 iBooster's 1.25" stroke so the pedal reaches full booster travel without the cylinder bottoming, with the 1-1/8" Wilwood master and Super Duty calipers at all four corners. Bench-measure on assembly.
• ARB RD140 fitment with Revolution F10.25-513L in the Sterling 10.5 housing (#300) — The rear runs a 10.25" ring gear (Revolution F10.25-513L) in the 10.5 housing with the ARB RD140 carrier (Ford 10.25/10.5, 35 spline, all ratios). Confirm with ARB or Revolution that the RD140 flange and ring gear bolt pattern match the F10.25 gear in this housing before ordering, and confirm the pinion depth starting point (owner note: add roughly 0.120" to the pinion depth stack).
• Ball joint delete clearance against ORA high steer arms (#299) — Verify the American Iron ball joint delete (upper and lower, welded) clears the Offroad Anonymous 05-16 Super Duty Dana 60 weld-on full hydro high steer arms through full steering travel (40 degree target with the 8" PSC ram) and full suspension travel.
• Front axle ball joint delete bushing offset (0 / 1.5 / 3 degree) (#298) — American Iron ball joint delete bushing offset sets caster and camber together, summing to the bushing rating. Select after caster is measured with the Dana 60 under the vehicle at ride height. Every 15 degrees of bushing rotation gives 0.5 degrees of change on a 3-degree set.
• 4WD/4LO indicator — NP241OR position switch → PMU → HDX (measure switch at teardown) (#145) — Reversed 2026-09-18 — the 4WD indicator is wanted after all. (Previously closed as "omit the indicator.") Updated the same day for the transfer-case change from JK NV241 to TJ/LJ Rubicon NP241OR (#313), which makes this easier.
• Turbolamik Aux: P/N (#48) — Confirm aux output channel + pinout configured for P/N (start interlock)
• Turbolamik Aux: Reverse (#47) — Confirm aux output channel + pinout configured for Reverse signal -> PMU In 3