Is the 2018 Mercedes-Benz Sl-Class reliable?

The 2018 Mercedes-Benz Sl-Class scores 72/100 (C-) on OwnerKeep's reliability index, which places it in the moderate risk category. See the full report for the specific strengths and failure points.

What are the common problems with the 2018 Mercedes-Benz Sl-Class?

See the Common Issues section above for the top failure areas reported by real owners, with typical mileage ranges where problems start showing up.

How much does it cost to maintain a 2018 Mercedes-Benz Sl-Class?

Expected maintenance costs depend heavily on age, mileage and how well the vehicle was kept up. Run the full report for a year-by-year cost outlook.

What should I check before buying a 2018 Mercedes-Benz Sl-Class?

Focus on the top risk areas flagged in this report, review service history, and verify the vehicle is not inside one of the mileage danger zones listed above.

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Reliability AnalysisBased on known issue patterns, repair cost data, and ownership trends · How we score

2018 Mercedes-Benz Sl-Class Reliability ReportCommon Problems, Repair Costs & Expert Verdict

72/ 100

KeepScore

MODERATE RISK

Grade: C-

A truly luxurious experience, but prepare for the potential of five-figure repairs if not properly managed.

Full system breakdown + what I would do

Quick Facts · 2018 Mercedes-Benz Sl-Class

No active NHTSA safety recalls on record — a clean recall slate for the 2018 model year.
Scores 7 points below the strongest nearby year — the 2016 Mercedes-Benz Sl-Class earns a 79.
The system most likely to surface first: active body control (abc) / airmatic suspension (major severity).

Should You Buy the 2018 Mercedes-Benz Sl-Class?

The 2018 Mercedes-Benz SL-Class offers exceptional luxury and performance, but its complex engineering brings a moderate risk profile for long-term ownership. While core components are generally robust, the advanced suspension and intricate electronics can lead to significant repair bills, demanding a proactive maintenance approach and a substantial repair budget.

Biggest Strengths

Robust M276/M278 engines (with proper maintenance)
High-quality interior materials and build integrity
Sophisticated 9G-Tronic transmission reliability

Top Risk Areas

The systems that break first on the 2018 Mercedes-Benz Sl-Class. Mileage windows, repair costs, and fix-before-you-buy notes are in the full report.

Active Body Control (ABC) / AIRMATIC Suspensionmajor

Electrical / Electronic Systemsmoderate

Engine Oil Leaks & Ancillary Failuresmajor

Typical mileage, cost ranges, and the exact what-to-check list are in the full report.

NHTSA Recalls

No active NHTSA safety recalls on file for the 2018 Mercedes-Benz Sl-Class. Always verify with your VIN atnhtsa.gov.

What breaks on the 2018 Mercedes-Benz Sl-Class?

Full reliability breakdown — engine, transmission, rust, electrical. With repair costs and mileage danger zones.

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Mercedes-Benz Sl-Class by Year

Compare KeepScores across nearby years of the Mercedes-Benz Sl-Class. Click any year for its full report.

All Mercedes-Benz Sl-Class years ranked →Mercedes-Benz Sl-Class years to avoid →Mercedes-Benz Sl-Class common problems →

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Frequently Asked Questions

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