Slotted above the medium-duty F-Series, the L-Series was produced over a wide variety of applications through its production life, including both straight trucks and semitractors.

Following the 1957 introduction of the C-series low-cab COE, Ford began to transition its heavy-truck lineup away from models derived from the F-Series line.

Derived from the C-Series, the H-Series mounted the cab higher on an all-new chassis with a forward-mounted axle (taking on the "Two-Story Falcon" nickname); while a Super Duty V8 was standard, the optional Cummins NH inline-6 was the first factory-installed diesel offered in a Ford truck.

[4] Similar in concept to the 1948-1956 "cab-forward" C-Series, the all-new design moved the cab upward and forward (the latter, to shorten the overall length of the vehicle).

A clean-sheet design (distinguished by its straight-edged design), the W-Series was offered solely with diesel engines; to save weight, an all-aluminum cab was offered as an option (alongside the standard steel cab)[5][6] At the end of the 1960s, Ford began construction of Kentucky Truck Assembly, adding a dedicated facility in Louisville for commercial truck production.

Coinciding with the construction of the assembly facility, Ford sought to consolidate the N-Series and the heavy F-Series into a single, all-new product line.

With the "L" in L-Series denoting its Louisville origins,[7] the new product line featured a larger cab, adding the front-hinged hood adopted by the Mack R-series, Kenworth W900, and Peterbilt 352.

For 1970, the L-series was introduced in four size ranges and two hood lengths and grille styles, and with single or tandem (denoted by the "T" in the model designation) rear axles.

Designed as a truck for long-haul drivers, the LTL-9000 was a competitor to the GMC General, Kenworth W900, Mack Super-Liner, and Peterbilt 359.

In the 1980 redesign of the medium-duty F- series, the hexagonal shape of the grille was carried over; it is a theme used in all Super Duty trucks since their 1998 introduction.

Other aerodynamic enhancements included skirted fuel tanks and a specially designed "Aero Bullet" sleeper unit.

[8] Following its introduction as a semitractor, the AeroMax line expanded into the vocational truck lineup alongside the rest of the Ford L series.

These featured optional full-length chassis skirting, along with the same aero headlights and bumpers of the older medium-hood LA series.

As was the case previously, the heavy-truck line was split into aerodynamically optimized semitractors (the newly renamed Aeromax 9500) and vocational/severe-service trucks.

1996 engines (Not all are shown) At the end of 1996, Ford completed the sale of its heavy-truck operations, selling the rights and production tools of the Louisville, Aeromax, and Cargo to Freightliner.