Currently, all versions of the Saf-T-Liner model line are produced in High Point, North Carolina.

Thomas offered its transit-style buses on a wide variety of chassis in comparison to other manufacturers (changing between Dodge, Ford, GMC, International Harvester, and Volvo).

In 1978, coinciding with an updated body design necessitated by federal school bus safety regulations, Thomas became a chassis manufacturer with the launch of the Saf-T-Liner EF and ER (EF=Engine Front, ER=Engine Rear).

[1] Serving as the replacement for the Saf-T-Liner ER and WestCoastER, the HD/HDX would use much of the same body, with the exception of the drivers' compartment forward.

To improve forward sightlines, all three sets of sideview mirrors (flat, convex, and blind-spot crossview) were integrated into single roof-mounted units, eliminating a number of brackets.

As part of the redesign, it was re-branded the EFX, bringing its naming in line with the rear-engine HDX model.

Standing for Maneuverability, Visibility, and Protection, the MVP series of the Saf-T-Liner represented their first substantial update.

Introduced as new series "All-Star" for 1991, the MVP represented Thomas's entry into lower-cost Type D school buses, a segment created by the Blue Bird TC/2000 and Wayne Lifestar, originally based on Oshkosh chassis.

Shortly after the introduction of the Saf-T-Liner ER, this variant was introduced by Thomas for West Coast markets (primarily California and Washington State).

However, as Crown Coach and Gillig both exited the school bus industry in the early 1990s, Thomas gained significant ground on the West Coast.