The design, finalized in December 1969,[4] was a dramatic leap forward, with more masculine lines that combined to create an elegant and sporty character.

The basic design concept continued the themes originally introduced on the R107 SL-Class roadster, especially the front and rear lights.

[1] As with the SL, the W116 received the ridged lamp covers which kept dirt accumulation at bay; this was to remain a Mercedes-Benz design theme into the 21st century.

The 450SE and 450SEL received a plusher interior, with velour or leather seats rather than the checkered cloth of the lesser models.

This model boasted the largest engine installed in a post-war Mercedes-Benz (and any non-American production automobile) up to that time,[7] and it also featured self-leveling hydropneumatic suspension.

Exclusive to the North American and Japanese markets was the 300SD, the world's first passenger car with a turbocharged diesel engine, which was introduced in 1978.

[8] The W116 became the first production car to use an electronic four-wheel multi-channel anti-lock braking system (ABS) from Bosch as an option from 1978 on.

In 1975, the W116 was upgraded with a new fuel injection system to comply with revised exhaust emission standards in European markets.

The early models (1973-1974) of the W116 with the twin cam inline 6 used the D-Jetronic fuel injection system with computers and MAP sensor that are both prone to failure after more than 20 years of use.

In 1977, the self-levelling rear suspension system was offered for 450SEL as an extra cost option outside the North American market.

[10] Due to the modifications demanded by the U.S. government, U.S. models of the Mercedes-Benz W116 were described by journalists as if a "beautiful car was beaten with the malaise ugly stick.