Car Model History

Second generation · W126 · 1981–1991

1981Mercedes-Benz S-Class

The best-selling classic S-Class and a design icon. It reached US showrooms for 1981 (late-1980 launch). The first production car offered with a driver's airbag; later added a passenger airbag (1988). Also spawned the C126 coupe (SEC).

Second generation · W126

1981 Mercedes-Benz S-Class (W126) — sedan, front three-quarter view

Photo: “1981 Mercedes-Benz 280 SE (W 126) sedan (25041740475)” by Jeremy from Sydney, Australia / Wikimedia Commons, licensed under CC BY 2.0. Cropped to 16:9.

Start here

What do you need to know?

This page covers the whole 1981 Mercedes-Benz S-Class model year. Choose your task first; exact trims and engines are separated where the factory offered different versions.

Complete, source-verified lineup

Find your exact 1981 S-Class

Start with a family, body style, or engine. Every card opens the facts and maintenance information for that factory version.

2factory configurations
Verified complete for the U.S.-marketHow this lineup was verified

We checked this U.S.-market lineup against period sources for factory sedan, coupe, cabriolet, drivetrain, and powertrain roster represented by the cited exact-year or factory-archive evidence. Every version shown below has its own detail page.

Verified 2026-09-01 from Mercedes-Benz Club of America — 1981–1991 W126 U.S.-market buyer's guide, Car and Driver — February 1981 U.S. 300 SD and 380 SEL launch test.

2versions shown
Four-door rear-wheel-drive luxury sedan

Mercedes-Benz 300 SD Automatic

Body
Four-door rear-wheel-drive luxury sedan
Engine
3.0-liter OM617 turbocharged diesel inline-five (125 hp)
Gearbox
4-speed automatic
Built
Regular production
Open exact version
Four-door long-wheelbase rear-wheel-drive luxury sedan

Mercedes-Benz 380 SEL Automatic

Body
Four-door long-wheelbase rear-wheel-drive luxury sedan
Engine
3.8-liter M116 fuel-injected V8 (155 hp U.S.)
Gearbox
4-speed automatic
Built
Regular production
Open exact version

The 1981 model year

Overview

The W126 reached the United States for model year 1981 as the turbodiesel 300 SD and long-wheelbase gasoline 380 SEL. Mercedes-Benz's factory history describes the W126 as an aerodynamically optimized, weight-reduced flagship with light-alloy V8 engines and deformable plastic bumpers, and dates the airbag's entry into automobile production to 1981.

Specifications

Engines
  • 3.0-liter OM617 turbocharged diesel inline-five (125 hp)
  • 3.8-liter M116 fuel-injected V8 (155 hp U.S.)
Transmissions
4-speed automatic
Body styles
Four-door rear-wheel-drive luxury sedan, Four-door long-wheelbase rear-wheel-drive luxury sedan

Year over year

What changed

  • The U.S. range changed completely from the outgoing W116 to the two-model W126 roster.
  • The 300 SD and 380 SEL separated diesel standard-wheelbase and gasoline long-wheelbase roles.

Worth knowing

Notable

  • Contemporary U.S. testing identifies the same 300 SD and 380 SEL launch pairing recorded in the club's model-year table.

Living with it

Reliability & ownership notes

  • Confirm the chassis, engine number, market specification, and build date before ordering parts; U.S. model-year rosters do not describe gray-market or other-market W126 sedans.
  • Use the maintenance record scoped to the exact engine shown on this page; it must not be projected onto the diesel, coupe, or other W126 powertrains that the source does not cover.

Maintenance & service parts

Keep your 1981 S-Class on the road

Start with the service interval, then match the engine or exact version you own. Order links appear only when a catalog-backed part number is available, and every listing still needs a fitment check.

Service desk

What this car needs & when

Use this as a service-planning checklist for 1981 Mercedes-Benz S-Class. Start with the interval, confirm which engine or configuration you have, then use an exact ordering reference when one is verified.

Service topics
6
Factory intervals
4
Fitment-scoped
6
Exact references
2

Before orderingIdentify your engine, options and build date.Part numbers and sizes can change within one model year. Shopping links appear only for catalog-backed references; still verify the listing against your vehicle before ordering.

  • Engine oil and filter

    Sourced interval available

    Applies to: 1981 · OM617 turbocharged diesel inline-five · 300 SD · United States · Exact 1981 300 SD owner's-manual schedule. It is not claimed for the gasoline 380 SEL.

    Published interval: 7,500 mi / 12,000 km / 12 months · Required every 7,500 miles or at least once a year.

    Source: Mercedes-Benz — 1981 300 SD owner's manual maintenance system · owner's manual pages 58–59 — engine oil and filter change · checked

  • Maintenance service

    Sourced interval available

    Applies to: 1981 · OM617 turbocharged diesel inline-five · 300 SD · United States · Exact 1981 300 SD owner's-manual schedule. It is not claimed for the gasoline 380 SEL.

    Published interval: 15,000 mi / 24,000 km / 24 months · Every 15,000 miles; for low-mileage operation, at least once every two years.

    Source: Mercedes-Benz — 1981 300 SD owner's manual maintenance system · owner's manual pages 58–59 — Mercedes-Benz Maintenance System · checked

  • Brake fluid

    Sourced interval available

    Applies to: 1981 · OM617 turbocharged diesel inline-five · 300 SD · United States · Exact 1981 300 SD owner's-manual schedule. It is not claimed for the gasoline 380 SEL.

    Published interval: 12 months · Replace annually, preferably in spring.

    Source: Mercedes-Benz — 1981 300 SD owner's manual maintenance system · owner's manual page 59 — special maintenance measures · checked

  • Engine coolant

    Sourced interval available

    Applies to: 1981 · OM617 turbocharged diesel inline-five · 300 SD · United States · Exact 1981 300 SD owner's-manual schedule. It is not claimed for the gasoline 380 SEL.

    Published interval: 36 months · Replace the water/anticorrosion-antifreeze mixture every three years.

    Source: Mercedes-Benz — 1981 300 SD owner's manual maintenance system · owner's manual page 59 — special maintenance measures · checked

  • Engine air filter

    Exact reference available

    The part reference below is catalog fitment only; retain the separately sourced factory service interval where one is shown.

    Applies to: 1981

    380 SEL — 3.8-liter M116 fuel-injected V8 (155 hp U.S.)

    K&N E-2872

    Applies to: 1981 · 3.8-liter M116 fuel-injected V8 (155 hp U.S.) · 380 SEL · Exact 1981 380 SEL engine application. Confirm VIN and build date before ordering.

    Source: K&N Engineering — 2017 European Automotive Catalog, S-Class application tables (archived copy) · W126 S-Class table — 380 SEL, 1981 — E-2872 · checked

    Verified ordering references

  • Engine oil filter

    Exact reference available

    Use the exact engine, VIN, and build date to confirm the catalogued service part before ordering.

    Applies to: 1981

    300 SD — 3.0-liter OM617 turbocharged diesel inline-five (125 hp)

    MAHLE OX 78D

    Applies to: 1981 · 3.0-liter OM617 turbocharged diesel inline-five (125 hp) · 300 SD · Exact 1981 300 SD engine application. Confirm VIN and build date before ordering.

    Source: MAHLE Aftermarket — Mercedes-Benz passenger-car filter application catalog · 1981 Mercedes-Benz 300SD 3.0L L5 — OX 78D · checked

    Verified ordering references

Collect

Bring this model year home

Find a scale model using the exact year, make, and model—not a generic generation search.

Sources

  1. Mercedes-Benz Media — factory S-Class history and W126 design/safety chronology
  2. Mercedes-Benz Club of America — 1981–1991 W126 U.S.-market buyer's guide
  3. Car and Driver — February 1981 U.S. 300 SD and 380 SEL launch test

Other Second generation years

Explore the W126 generation →All Second generation · W126 years →

Browse by tag

← All Mercedes-Benz S-Class years