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Beach BenzMercedes-Benz Specialist
sedan · 1972–1980

W116

450SEL / 450SEL 6.9 S-Class

Reliability: Good
3 engines5 known issues

Overview

The W116 was the first Mercedes-Benz to officially carry the S-Class name. It set the standard for luxury sedans worldwide with its refined ride, advanced safety features, and imposing road presence. The flagship 450SEL 6.9 featured a hydropneumatic self-leveling suspension and the largest passenger-car engine Mercedes offered at the time, making it one of the fastest sedans in the world.

Engines & Transmissions

Engine Options

  • M110 2.8L I6
  • M117 3.5/4.5L V8
  • M100 6.9L V8 (6.9 only)

Transmissions

  • 4-speed manual
  • 722.3 3-speed automatic
  • 722.3 4-speed automatic

Common Problems

Known issues reported across the W116 production run, ordered by severity. These are based on our direct experience servicing these vehicles over 35 years.

Maintenance Highlights

Key service intervals for the W116. These are based on our recommended schedule for Southern California driving conditions, which may differ from factory-specified intervals.

Engine oil & filter (semi-synthetic)
Every 3,000 miles
Hydropneumatic suspension fluid and accumulator check (6.9)
Every 15,000 miles
K-Jetronic fuel distributor inspection and calibration
Every 20,000 miles
Timing chain and tensioner inspection
Every 30,000 miles

Reliability Assessment

B
Good Reliability

Based on 35 years of service data at Beach Benz

PoorFairGoodExcellent

Beach Benz Experience

From Our Technicians

The W116 is where the modern S-Class story begins, and we have been maintaining them since they were nearly new. The 450SEL 6.9 is a very special machine — the hydropneumatic suspension gives an unmatched ride when it is working correctly, and we have developed a reliable rebuild procedure over 35 years of working on these systems. For the standard V8 models, the K-Jetronic fuel injection is the number one concern. We rebuild fuel distributors in-house and can usually resolve drivability issues in a single visit.

— Beach Benz service team · 35+ years of Mercedes-Benz specialization

W116 Specialist

Your W116 deserves a specialist.

Factory diagnostics. OEM parts. 35 years of Mercedes-Benz expertise. Whether it's a routine service or a complex repair, Beach Benz has your W116 450SEL / 450SEL 6.9 S-Class covered.

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