Should I check the MOT history before buying a 2018 Mercedes Benz Sl?

Yes. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. A full MOT history analysis will highlight patterns that a single test result won't reveal.

What corrosion should I look for when inspecting a 2018 Mercedes Benz Sl?

Check brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that is expensive to fix and can fail an MOT.

How are tyres and brakes typically on a 2018 Mercedes Benz Sl?

Tyres and brakes are the most common advisory items on vehicles of this age. Budget for replacement if they are near the limit, and factor this into your offer price.

Is the 2018 Mercedes Benz Sl reliable?

Based on MOT data from 407 vehicles, the 2018 Mercedes Benz Sl has a first-time MOT pass rate of 93.5%, indicating generally reliable for its class. Always check the full MOT history of any specific vehicle before buying.

What are common problems with the 2018 Mercedes Benz Sl?

The most frequently recorded MOT issues on the 2018 Mercedes Benz Sl are: Nearside Rear Tyre worn close to legal limit/worn on edge (22% of vehicles), Offside Rear Tyre worn close to legal limit/worn on edge (22% of vehicles), Offside Front Tyre slightly damaged/cracking or perishing (14.8% of vehicles). These figures are based on actual MOT test records — search a specific registration on CarHunch to see its individual history.

Do I need an HPI check when buying a 2018 Mercedes Benz Sl?

Yes. The MOT history will not show outstanding finance, insurance write-offs, or stolen status. An HPI check covers these areas and should be part of any used car purchase.

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Mercedes Benz Sl (2018)

407 real MOT outcomes analysed • 93.5% first-time pass rate

2018 Mercedes Benz Sl

CarHunch analysed 407 real MOT records for the 2018 Mercedes Benz Sl. Real test outcomes — pass rates, defect profiles, mileage data — from verified DVLA records. Updated as new MOTs are recorded.
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AI Analysis Reliability Overview Common Issues Check a Specific Reg Buyer's Checklist Mileage Distribution Still on the Road MOT Averages Colour Breakdown Compare Models

Moderate sample. 407 vehicles on record. Figures are indicative — the specific vehicle's history matters more than these averages.

The 2018 Mercedes-Benz SL is a genuinely reliable performer: 93.5% of cars pass their MOT first time, well above the UK average of 80%, and only 18.4% have ever recorded a dangerous defect—a respectable figure for a premium sports car. You can buy with confidence on the mechanical front.

These cars are running low mileage for their age (median 18,984 miles), which helps explain the strong pass rate, but it also means you're getting relatively lightly-used examples. The average vehicle racks up just 0.42 failures and 2.4 advisories per MOT, suggesting routine maintenance is being kept on top of; before you buy, ask for full service history to confirm that pattern has held.

The 2018 Mercedes Benz Sl passes its MOT first time at roughly the UK average rate (93.5%) — solid but worth checking this vehicle's history carefully.

⚠️ Around 1 in 8 of these vehicles have had a dangerous MOT failure at some point — usually tyres or brakes, and often a one-off issue rather than a persistent problem. The group stats won't tell you which one you're looking at.

First-time pass

93.5%

UK average ~80%

Better than average

Dangerous (ever)

18.4%

At least once in MOT history

Check this vehicle

Avg failures / car

0.42

Over 5.5 tests on record

Low

Typical mileage

19k

Middle half: 12k–27k

For context

✅ Good baseline reliability. A 93.5% first-time pass rate puts this well above the UK average — it's a well-sorted vehicle in this age bracket.

🔧 Expect consumable spend. An average of 2.4 advisories per vehicle tells you wear items (tyres, brakes) get flagged regularly. Budget for them — they're not surprises.

🔍 The dangerous defect figure is real. Most are one-off tyre failures or brake issues — not structural problems. But it's exactly why checking the individual vehicle's history is essential, not optional.

These stats describe 407 vehicles as a group. The specific vehicle you're looking at could be the one good example or the one outlier. Run its registration to find out.

Average reliability — agree?

What tends to go wrong

Across 407 vehicles — figures show how many had each issue flagged at least once in their MOT history.

Tyre wear 22%

Nearside Rear Tyre worn close to legal limit/worn on edge · Offside Rear Tyre worn close to legal limit/worn on edge · Offside Front Tyre slightly damaged/cracking or perishing · …

Budget for a full set — on a vehicle this age, tyres are expected consumables. An inspection will confirm how much is left.

Other issues 12.6%

COVID-19 6 MONTH EXTENSION · Windscreen damaged but not adversely affecting driver's view

Brake wear 6.3%

Rear Brake pad(s) wearing thin · Front Brake pad(s) wearing thin

Ask the seller when brakes were last serviced. If they don't know, factor in the cost.

Suspension & steering 4.5%

Nearside Front Lower Suspension arm ball joint has slight play

Harder to spot without a ramp — this is a good reason to book a pre-purchase inspection.

Lighting 4.5%

Nearside Front Road wheel slightly distorted

Usually cheap to fix. Worth confirming all lights work before collecting.

Data covers a 3-year window centred on 2018.

See this vehicle's full MOT history & AI hunches

Spot recurring advisories, hidden issues, and how it compares to 407 Mercedes Benz Sl cars.

Before you buy a 2018 Mercedes Benz Sl

Based on MOT data from 407 vehicles — here's what to check.

📋 Check the full MOT history. 18.4% of these vehicles have had a dangerous defect recorded - recurring advisories often signal problems years before they become failures.
Search the reg on CarHunch for the full MOT history, reliability stats and a free AI-powered analysis of that exact vehicle.
🔍 Brake pipes, sills and subframes are the key areas on a vehicle this age — structural rust is hard to spot without getting underneath. A mechanic will check all of this before you commit, and give you a concrete basis to negotiate on price. Inspection →
📄 Outstanding finance, insurance write-offs and clocking won't appear in the MOT records — a dedicated history check covers all of this. Our link gets you 20% off automatically. History Get 20% off via CarHunch

Colour Breakdown

Based on 34,567 Mercedes Benz Sl vehicles registered in the UK — across all years. From DVLA registration records.

Silver 33.9%

11,735

Black 24.1%

8,343

Blue 17.8%

6,160

Red 8.5%

2,946

White 6.2%

2,160

Grey 3.7%

1,270

Green 3.5%

1,202

Gold 1%

341

Brown 0.4%

125

Cream 0.3%

106

Beige 0.3%

104

Yellow 0.2%

Mileage Distribution

Most 2018 Mercedes Benz Sl vehicles sit in the blue band. If the vehicle you're looking at is outside it, it's either unusually low or high mileage for its age.

18,984

typical

12,327

low mileage

27,321

high mileage

Half of all 2018 Mercedes Benz Sl vehicles fall between 12,327 and 27,321 miles.

Is the mileage you're seeing normal?

✓ Under 12,327 miles — lower than most. Could be great, or could be a vehicle that rarely moved. Check test frequency and mileage progression in the MOT history.

✓ 12,327–27,321 miles — normal for age. This is where most 2018 Mercedes Benz Sls sit.

⚠ Over 36,883 miles — higher than typical. Not necessarily a problem, but check service history and look out for advisory build-up on tyres and brakes.

2018 Mercedes Benz Sl — Still on the Road

Almost all 2018 Mercedes Benz Sls are still on the road.

Strong survival — 385 vehicles still getting MOTs in 2025, 97% of the peak.

Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2021–2025.

MOT History Averages

5.5

Avg MOT tests per vehicle

0.42

Avg failures per vehicle

2.4

Avg advisories per vehicle

Other model years — Mercedes Benz Sl: All Sl years → Which year to buy? →

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Average reliability — agree?