MERCEDES 300 (1990)
Running costs, reliability data, and common problems from 947 real MOT tests.
Annual Cost
£2,427
£202/month
MOT Pass Rate
84%
Good
Road Tax
£430
Based on CC/year
Insurance
Grp 30-42
2968cc Petrol
Solid Option
84% pass rate, £2427/year to run. Close to the national average.
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Annual Running Costs
~30 mpg
Based on 2968cc
Based on 7,400 miles/year (UK average), current fuel prices, and repair likelihood from MOT data. Insurance not included.
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Reliability Verdict
Good reliability. Occasional issues but generally solid. That's close to the national average of 82%.
At 36 years old, 84% of MERCEDES 300s from 1990 passed their MOT first time in 2026. That's based on 947 tests across the UK. The average mileage at this age is 126,597 miles.
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Mileage Analysis
126,597
Average miles
266,400
Expected for age
The average 1990 MERCEDES 300 has 126,597 miles on the clock, which is significantly below the expected 266,400 miles for a 36-year-old car. Low-mileage examples may have spent time sitting unused, so check for issues like corroded brakes or perished rubber seals.
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MERCEDES 300 by Year
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About the 1990 MERCEDES 300
The 1990 MERCEDES 300 is a large car with a 2968cc petrol engine. 947 of these vehicles were MOT tested in 2026, making it a less common model in the UK market. Among all cars from 1990, the average MOT pass rate is 79%, and this model beats that benchmark.
With an average of 126,597 miles at 36 years old, MERCEDES 300 owners tend to use this car less than the typical driver. Very low mileage could mean the car has been garaged or used only for short trips, which can cause its own issues like battery drain and moisture buildup.
1990 MERCEDES 300 Fuel Costs
The 2968cc petrol engine is on the larger side, so fuel won't be this car's strong point. Expect around 30 mpg in mixed driving, which works out to roughly £1,592 per year at current petrol prices of 142p per litre (based on 7,400 miles per year).
What does it cost to own a 1990 MERCEDES 300?
Total estimated annual running cost is £2,427 (£202/month), broken down as £1592 fuel, £430 road tax, £55 MOT, and £350 predicted repairs. Repair costs are moderate, reflecting the 84% pass rate. Keeping on top of servicing will help avoid surprises.
MERCEDES 300 Reliability Trend
The MERCEDES 300 has maintained consistent MOT pass rates across model years, varying by only 0 percentage points.
Buying a Used 1990 MERCEDES 300
At 36 years old, the MERCEDES 300 is firmly in budget territory. Purchase prices are low, but check for rust, worn suspension bushes, and electrical gremlins. A full service history is especially valuable at this age.
Common Issues to Watch For
Based on the 1990 MERCEDES 300's fuel type, age, and engine size, these are the most likely problem areas to check.
Timing Chain / Belt
Watch outAt 36 years old, check whether the timing belt has been replaced (typically due every 5-7 years or 60,000-100,000 miles). A snapped belt can destroy the engine.
Oil Consumption
Medium riskLarger petrol engines can develop higher oil consumption as they age. Check the oil level and look for blue smoke from the exhaust.
Rust and Corrosion
Watch outAt 10+ years, check wheel arches, sills, subframe, and brake lines for rust. Structural corrosion is an MOT failure. Prevention is far cheaper than repair.
Suspension Bushings
Watch outRubber suspension bushes harden and crack with age, causing knocking noises and vague handling. A full refresh costs £300-£800 depending on the car.
Clutch Wear
Watch outWith an average of 127k miles, clutch replacement may be due (typical lifespan 60,000-100,000 miles). Budget £400-£800 for a new clutch kit.
Brake Discs and Pads
Medium riskHigh-mileage cars often need brake disc replacement, not just pads. A full set of discs and pads costs £200-£500 per axle.
Engine Mounts
Medium riskWorn engine mounts cause excessive vibration and movement. Replacement costs £150-£400 per mount. Check for vibration at idle with the bonnet open.
Service History
Low riskAlways request a full service history. Regular servicing is the single best indicator of how well a car has been maintained, regardless of mileage.
Running Costs Compared
How the 1990 MERCEDES 300 stacks up against similar cars for annual running costs, insurance, and tax.
| Car | Pass Rate | Fuel/yr | Tax/yr | Insurance | Total/yr |
|---|---|---|---|---|---|
| MERCEDES 300(1990) | 84% | £1592 | £430 | Grp 30-42 | £2427 |
| PORSCHE 911(1991) | 91% | £1592 | £250 | Grp 35-50 | £2097-£330 |
| PORSCHE 944(1990) | 85% | £1592 | £250 | Grp 30-42 | £2247-£180 |
| MERCEDES SL(1992) | 87% | £1592 | £250 | Grp 30-42 | £2247-£180 |
| MERCEDES 260(1992) | 78% | £1592 | £250 | Grp 30-42 | £2397-£30 |
Estimates based on 7,400 miles/year, current fuel prices, and MOT data. Insurance groups are indicative. Actual costs vary by driver, location, and usage.
Related Mercedes Models
Explore other Mercedes cars or similar models in the same category.
MERCEDES A
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MERCEDES C
2017 · 1991cc Hybrid
MERCEDES A-CLASS
2017 · 1461cc Diesel
PORSCHE 911
1991 · 3164cc Petrol
PORSCHE 944
1990 · 2969cc Petrol
MERCEDES SL
1992 · 2960cc Petrol
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