In 1972, the GTO reverted from a separate model line to a $353.88 option package for the LeMans and LeMans Sport coupes. On the base LeMans line, the GTO package could be had with either the low-priced pillared coupe or hardtop coupe. Both models came standard with cloth and vinyl or all-vinyl bench seats and rubber floor mats on the pillared coupe and carpeting on the hardtop, creating a lower-priced GTO. The LeMans Sport, offered only as a hardtop coupe, came with Strato bucket seats upholstered in vinyl, along with carpeting on floor and lower door panels, vinyl door-pull straps, custom pedal trim and cushioned steering wheel, much like GTOs of previous years. Other optional equipment was similar to 1971 and earlier models. Planned for 1972 as a GTO option was the ducktail rear spoiler from the Pontiac Firebird, but after a few cars were built with that option, the mold used to produce the spoiler broke, and it was cancelled. Rally II and honeycomb wheels were optional on all GTOs, with the honeycombs now featuring red Pontiac arrowhead emblems on the center caps, while the Rally IIs continued with the same caps as before, with the letters "PMD" (for Pontiac Motor Division).
Power, now rated in SAE net hp terms, was down further, to 250 hp at 4,400 rpm and 325 lb·ft at 3,200 rpm torque for the base 400 engine. The optional 455 had the same rated power (although at a peak of 3,600 rpm), but substantially more torque. Most of the drop was attributable to the new rating system (which now reflected an engine in as-installed condition with mufflers, accessories, and standard intake). The engines were relatively little changed from 1971.
A very rare option was the 455 HO engine, essentially similar to that used in the Trans Am. It was rated at 300 hp at 4,000 rpm and 415 lb·ft at 3,200 rpm, also in the new SAE net figures. Despite its modest 8.4:1 compression, it was as strong as many earlier engines with higher gross power ratings; yet like all other 1972-model engines, it could perform on low-octane regular leaded, low-lead or unleaded gasolines. Only 646 cars with this engine were sold.
Sales plummeted by 45%, to 5,811. (Some sources discount the single convertible and the three anomalous wagons, listing the total as 5,807.) Although Pontiac did not offer a production GTO convertible in 1972, a buyer could order a LeMans Sport convertible with either of the three GTO engines and other sporty/performance options to create a GTO in all but name. Even the GTO's Endura bumper was offered as an option on LeMans/Sport models, with "PONTIAC" spelled out on the driver's side grille rather than "GTO."
