Powertrain families
M30 petrol I6
7 Series (E23) — Sedan
1977–1986
Editorially reviewedReviewed 2026-08-10; market and model-year scope is stated in the record sources.
- Internal code
- E23
- Production
- April 1977 – June 1986
- Body style
- 4-door sedan
- Platform
- longitudinal layout · rear-wheel drive
Body variants
7 Series → E23 → Sedan
7 Series E23: history, design and engineering
How this generation came about, what made it different and how the selected sedan fits into the family.
E23 established the 7 Series as BMW's permanent luxury flagship in 1977. It replaced the large E3 saloons with a clearer identity of its own and combined a formal four-door body with the driver-oriented dashboard and straight-six engines familiar from other BMWs.
The generation became a showcase for equipment that was still unusual in European cars, including increasingly sophisticated climate, trip-computer and electronic-control systems. At the top, the turbocharged 745i offered a distinctly BMW alternative to a larger-capacity engine, though its specification varied by market.
E23 remained one standard-wheelbase four-door shell throughout factory production. The North American L7 was a high-equipment derivative rather than a stretched limousine, while South African and European performance versions used different engines and emissions specifications. Early carburettor, injection, Motronic and turbocharged cars therefore need separate market and production-date rows.
1977–1986generation lifecycle
1body branches
1engine/drive families
7range designations
E23factory code
longitudinal layout · rear-wheel drivearchitecture
Sedan: dimensions and packaging
Dimensions can change with body, market and model year, so this page keeps them tied to the exact factory branch.
Length4,860 mm
Width1,800 mm
Height1,430 mm
Wheelbase2,795 mm
Luggage≈ 481 L
Fuel tank100 L
Seats5
Doors4-door sedan
| Body | Code | Production | Doors / seats | Length | Luggage |
|---|---|---|---|---|---|
| Sedan | E23 | 1977–1986 | 4-door sedan / 5 | 4,860 mm | ≈ 481 L |
Engines and powertrains
The generation could span very different engines and drivetrains. The table keeps output, gearbox, market and production period together.
Factory modification matrix
Documented sedan applications; output and availability remain market- and model-year-specific.
| Model | Years | Engine | Output | Transmission | Drive | Market | Source |
|---|---|---|---|---|---|---|---|
| 728 / 728i | 1977–1986 | M30B28 | 170–184 PS | 4MT / 5MT / 3AT / 4AT | RWD | Europe | BMW 7 Series Sedan (E23) |
| 730 | 1977–1979 | M30B30 | 184 PS | 4MT / 3AT | RWD | Europe | BMW 7 Series Sedan (E23) |
| 732i / 733i | 1977–1986 | M30B32 | 197 PS | 4MT / 5MT / 3AT / 4AT | RWD | Global range | BMW 7 Series Sedan (E23) |
| 735i | 1979–1986 | M30B35 | 218 PS | 5MT / 4AT | RWD | Global range | BMW 7 Series Sedan (E23) |
| 745i | 1980–1986 | M102 / M106 turbo I6 | 252 PS | 3AT / 4AT | RWD | Europe | BMW 7 Series Sedan (E23) |
| 733i / 735i (US) | 1977–1986 | M30 petrol I6 | 181–182 hp | 5MT / 3AT / 4AT | RWD | North America | BMW 7 Series Sedan (E23) |
Factory designations
728 · 728i · 730 · 732i · 733i · 735i · 745i
Petrol engines
Inline and V engines are grouped by engine family, displacement, induction system and emissions specification.
Diesel derivatives
Where diesels were offered, output, injection generation and emissions hardware are recorded market by market.
How power reaches the road
Gearboxes, driven wheels and final-drive hardware changed with engine, market and production date.
Transmissions
Gearbox type and unit code follow engine, market and production date. Gear count alone does not identify the transmission.
Driven wheels
Catalog architecture: longitudinal layout · rear-wheel drive. All-wheel-drive availability and hardware remain derivative-specific.
Final drive
Ratio, differential type and electronic control belong to the exact derivative and can differ on performance models.
What changed underneath
Suspension, brakes, safety systems and electronics evolved across the range, even when cars shared the same basic architecture.
Body-branch dimensions
- E23: 4,860 mm × 1,800 mm × 1,430 mm
Body & suspension
- Mounting points and geometry follow the body branch
- Springs and dampers follow axle load and chassis package
- Wheels and permitted loads follow the factory label
Brakes & steering
- Brake size follows engine and equipment
- Assistance type and steering ratio can change
- ABS/DSC generation follows model year
Passive safety
- Airbag count varies by market and year
- SRS parts are VIN-specific
- Structural repairs require factory procedures
Electronics
- Vehicle-bus generations changed during production
- Control-unit software levels must remain compatible
- Retrofits are recorded separately from factory equipment
How the generation evolved
The important launches, additions and updates did not always happen at the same time for every body or market.
First 7 Series
728, 730 and 733i launched the E23 range.
Injection and turbo
Injection replaced the entry carburettor models and 745i became the turbocharged flagship.
Major model revision
Revised exterior and cabin details accompanied updated electronic engine management and model designations.
Production end
E23 production ended in June before E32 assumed the flagship role.
The versions that stood apart
Performance models, option packages and regional editions may look related, but their engineering and production identity can be very different.
Sedan
E23The sole E23 factory body was a four-door luxury sedan on the platform related to the contemporary E24 6 Series. Engines/drive: M30 petrol I6.
Inside the car
Cabin technology and standard equipment changed by country and year; a build sheet remains the best guide to one individual car.
Cabin & comfort
- Trim and seats follow option codes
- Climate systems vary by market
- Audio and navigation changed by model year
Lighting & assistance
- Lamp technology and modules follow production date
- Driver assistance cannot be inferred from buttons alone
- Regional rules affect lighting and warnings
What to check today
A practical starting point for inspecting and maintaining a car from this generation — not a diagnosis of an individual example.
Identify first
- Match VIN on body and documents
- Obtain the factory option list
- Confirm market and production date
Inspect the structure
- Check repairs and corrosion
- Assess suspension, brakes and tyres
- Compare fitted parts with factory specification
Mechanical history
- Read faults with compatible diagnostics
- Verify engine and transmission maintenance
- Separate invoices from unsupported verbal history
| Item | Interval / trigger | Catalog note |
|---|---|---|
| Engine oil & filter | CBS/factory schedule; time and mileage for historic cars | Oil approval follows the exact engine and market. |
| Brake fluid | Time-based factory schedule | ABS/DSC-compatible bleeding procedure is required after hydraulic work. |
| Coolant | Factory schedule and condition | Fluid specification and bleeding method are generation-specific. |
| Transmission & final drives | Unit type and operating conditions | Use the exact approved fluid; no one interval fits every derivative. |
How to identify the exact car
The badge and registration year tell only part of the story; production date, body code, engine and factory options complete it.
- Factory body codes
- E23 — Sedan
- Range designations
- 728, 728i, 730, 732i, 733i, 735i, 745i
- Powertrain families
- M30 petrol I6
- VIN
- Identifies model, plant and production branch and keys the parts catalog and factory equipment record.
- Production date
- More useful than first-registration year when choosing parts and locating technical revisions.
- Type code
- Refines engine, body, market and transmission combination.
- Option codes
- Confirm factory equipment; later retrofits are recorded separately.
- Unit number
- Supports engine or gearbox originality checks and component applicability.
Where the information comes from
The story is mapped through English Wikipedia and its bibliography, then important dates and technical claims are checked against BMW material.
- 01BMW 7 Series (E23)Wikipedia contributors
English-language secondary overview of the generation, body programme, powertrains and production chronology; key claims are cross-checked against the factory sources below.
- 02BMW 7 Series Sedan (E23)BMW Group Classic
Official body, platform and production history.
Notes and limitations
- Standard, iL/Li and the single G70 body are different body-level records; Executive or Highline equipment does not create a new body.
- Output, transmission and equipment depend on market and production date and require VIN-linked, dated factory literature.
2 primary references · market differences documentedPhotography: OSX, Public domain · Wikimedia Commons. Rights checked 2026-08-06; wikimedia commons 1,800 px derivative downloaded; local 640 px and 1,280 px avif versions created without cropping.Updated 6 August 2026