1991 Ford LN8000 Service and Repair Manual
This factory service and repair manual for the 1991 Ford LN8000 covers two turbocharged inline-six diesels, the 7.8L (473 cu in) and the 6.6L (401 cu in), in a short-conventional tractor or straight truck sold in a single Base trim. The manual gives each engine its own procedures, specifications and torque values and provides wiring diagrams and diagnostics for both chassis, so the tractor and the straight truck are equally covered.
Engines covered
- 7.8L inline-six (473 cu in) — turbocharged, diesel
- 6.6L inline-six (401 cu in) — turbocharged, diesel
Body styles covered
- Tractor truck, short conventional
- Straight truck, short conventional
Trims covered
- Base
Known issues on the 1991 LN8000. Both turbocharged inline-sixes stay on the books for the LN8000, the 7.8L and the 6.6L, where the lighter LN7000 lists only the smaller of them, so this manual has to carry two sets of injection, boost and cooling specifications instead of one. Tractor and straight-truck versions of the short conventional are covered together, which splits the driveline and frame sections. NHTSA's record for the year is empty of recalls and of owner complaints.
