Mercedes-Benz S-Class problems
Light NHTSA footprint — 29 owner complaints. Either a clean record or thin data; we'll show what's there.
Solid reliability overall. Common issues are concentrated in a few systems.
Buyable on the data — keep up the usual maintenance and inspect normally.
- No systemic severe-failure pattern in the complaint record
- Reliability score 8.4/10 — above the segment average
Our read of the federal NHTSA complaint and recall record for this exact year and model — not a substitute for a pre-purchase inspection. How we score.
Buying a used 2018 Mercedes-Benz S-Class? Check these first
Here's what this model is known to do — so you can inspect for it, price it in, or make the seller fix it before you sign.
What to inspect on this specific car
- engine — 6 owner reports · tends to show around 39,000 mi · ~$3,100 to fix
- steering — 5 owner reports · tends to show around 3,800 mi · ~$700 to fix
- brakes — 4 owner reports · tends to show around 22,533 mi · ~$450 to fix
⚠ The one to take seriously: engine is flagged severe on this model , showing up around 39,000 mi. Inspect it closely on a test drive.
Recalls to confirm are done
Run the VIN from the listing — no active recalls on this model right now, but confirm none were opened after this car was built.
Verdict for buyers: 8.4/10 model. The priciest documented failure is engine (~$3,100) — get the seller's service records for it or inspect closely. Otherwise an average-risk used buy at a fair price.
We tell you what this model is known for and what to inspect — a vehicle-history report tells you what this exact car has been through. Smart buyers get both.
See the full pre-purchase inspection checklist →Ask anything about your 2018 Mercedes-Benz S-Class
A noise, a warning light, a repair quote, "should I buy this?" — get an answer grounded in this vehicle's actual NHTSA record, not generic advice.
Answers use this vehicle's NHTSA complaint & recall record — owner-reported and unverified, not a diagnosis. Verify anything safety-critical with a mechanic.
Top trouble spots 3 categories with 3+ complaints
What owners are saying recent NHTSA-filed complaints · verbatim
The pre-collision safety feature goes off when there is no collision imminent. It is frightening and could actually cause an accident.
Vehicle had a low tire, vehicle indicated it needed to be driven for recalibration of the sensor(s). Took vehicle for short drive up two lane road. Turned around and headed back to where was staying and upon acceleration the vehicle seemed to have pulled off the road but come…
Tl* the consumer owned a 2018 Mercedes-benz s560. After driving the vehicle for approximately three minutes, the contact parked the vehicle. The consumer was alerted by someone that there was smoke under the hood of the vehicle. Within thirty seconds to a minute, the vehicle…
The Smell of fuel is present inside the vehicle around 50 percent of the time. When parked in the garage the vehicle emits an extremely strong fuel smell as if it has leaked fuel with no visible spills or leaks. While driving the smell of fuel is present almost always.
Estimate your repair exposure
Drag to your current mileage. Numbers are derived from this vehicle's complaint history.
Common questions
Is the 2018 Mercedes-Benz S-Class reliable?
Mostly yes. With a reliability score of 8.4 out of 10 based on 29 owner complaints filed with NHTSA, the 2018 Mercedes-Benz S-Class is generally a sound vehicle. The areas to watch are listed in the top problem section above — most are budget items, not deal-breakers.
Should you avoid the 2018 Mercedes-Benz S-Class?
On the NHTSA data, the 2018 Mercedes-Benz S-Class does not need avoiding. Buyable on the data — keep up the usual maintenance and inspect normally. The record behind that call: No systemic severe-failure pattern in the complaint record; Reliability score 8.4/10 — above the segment average. This is our read of the federal complaint and recall data — not a substitute for a pre-purchase inspection.
What should I check before buying a used 2018 Mercedes-Benz S-Class?
Inspect the engine first — it's the most-reported issue on this model, with 6 owner complaints filed. Typical failure occurs around 39,000 miles. Average repair cost runs about $3,100 at an independent shop. Also confirm any open recalls have been completed by running the VIN, and ask for service records covering the problem areas listed above.
Is the 2018 Mercedes-Benz S-Class a good used car to buy?
It scores 8.4 out of 10 on our NHTSA-based read of 29 owner complaints. The main thing to watch is engine. Typical failure occurs around 39,000 miles. Priced fairly and clean on inspection, it's a reasonable used buy. Our data covers what this model is known for — pair it with a vehicle-history report on the VIN to see what that specific car has been through.
What's the most common problem on the 2018 Mercedes-Benz S-Class?
Based on NHTSA records, the most-reported issue is engine, with 6 complaints filed. Typical failure occurs around 39,000 miles. Average repair cost runs about $3,100 at an independent shop.
What's the most expensive thing that goes wrong?
The engine is one of the costlier repair items. Average repair cost runs about $3,100 at an independent shop. Typical failure occurs around 39,000 miles. Catching early warning signs can sometimes extend life by 20–30,000 miles.
How do I check if my Mercedes-Benz S-Class has open recalls?
Paste your VIN into the decoder at the top of this page. We pull live from NHTSA, so you'll see exactly which campaigns apply to your vehicle and whether the dealer has logged the fix. Recall repairs are always free regardless of mileage or warranty status.
Is an extended warranty worth it on a 2018 Mercedes-Benz S-Class?
Math is straightforward: a quality service contract runs $1,800–3,500 over 3 years. With 29 complaints on file and the costliest repair averaging $3,100, one major failure more than pays for it. The catch is reading the contract — many providers exclude wear items and require pre-authorization, so cheaper plans are not always better value.