CarVerify

Triumph Stag Reliability, MOT Pass Rate & Common Faults

Free Triumph Stag car check

Is the Triumph Stag reliable? We analysed 64,590 real MOT tests across 6,070 vehicles to find out.

Got a specific Triumph Stag? Enter the reg for a free check:

Free basic check Reports from £4.99 Results in seconds
Data last updated: · Based on 64,590 real MOT tests
MOT Pass Rate
77.5%
Typical Mileage
56,548mi
Annual Mileage
417mi/yr
Est. Lifespan
56yrs

The Triumph Stag is above average for reliability based on real UK MOT data. Common problems include windscreen washer provides insufficient washer liquid, parking brake: efficiency below requirements and suspension component mounting prescribed area is excessively corroded. Here's everything you need to know before buying a used Triumph Stag.

Triumph Stag Number Plates

Number plates registered to a Triumph Stag. Click on any registration for full vehicle details — including MOT history, mileage records, previous owners and damage history.

Triumph Stag MOT Pass Rate by Year

How likely is a Triumph Stag to pass its MOT? Here's the pass rate for each registration year, newest first.

71.4%
1995
88.5%
1994
78.6%
1990
83.1%
1989
79.7%
1988
74.6%
1987
82.6%
1984
85.7%
1982
74.1%
1981
74.8%
1980
81.3%
1979
75.5%
1978
77.7%
1977
75.5%
1976
76.4%
1975
78.3%
1974
77.9%
1973
78.5%
1972
77.2%
1971
79.3%
1970

Triumph Stag Problems — What Goes Wrong?

The most common reasons a Triumph Stag fails its MOT, ranked by how often they occur. Check for these problems before you buy.

Windscreen washer provides insufficient washer liquid 2,039
Parking brake: efficiency below requirements 1,744
Suspension component mounting prescribed area is excessively corroded 1,507
Stop lamp not working 1,283
brake binding 1,269
Windscreen wiper does not clear the windscreen effectively 954
parking brake recording little or no effort 880
Exhaust emissions carbon monoxide content excessive 840
Headlamp not working on main beam 780
Headlamp not working on dipped beam 745

Triumph Stag Mileage — What's Normal?

How many miles does a typical Triumph Stag owner drive per year? Use this to check if a car you're looking at has suspiciously low or high mileage.

Low usage
138 mi/yr
Typical
417 mi/yr
Average
986 mi/yr
Heavy usage
979 mi/yr

Triumph Stag MOT Data by Registration Year

Full breakdown of pass rate and mileage for each year. Use this to compare the Triumph Stag year you're looking at.

Year Tests Pass Rate Low Mi. Typical Mi. High Mi.
1995 56 71.4% 26,292 54,176 56,625
1994 52 88.5% 11,646 64,695 76,471
1990 70 78.6% 36,378 45,668 51,370
1989 71 83.1% 34,416 49,355 51,763
1988 74 79.7% 12,315 19,100 51,152
1987 63 74.6% 52,797 70,817 77,198
1984 69 82.6% 47,899 80,204 86,132
1982 70 85.7% 37,272 52,852 58,046
1981 162 74.1% 44,530 58,997 80,586
1980 103 74.8% 19,812 40,373 71,702
1979 171 81.3% 17,730 39,638 60,759
1978 2,710 75.5% 35,588 62,190 78,376
1977 6,546 77.7% 34,062 60,708 78,760
1976 8,202 75.5% 25,648 57,333 79,846
1975 5,791 76.4% 20,099 54,677 77,278
1974 9,750 78.3% 21,451 57,450 79,032
1973 10,065 77.9% 20,918 53,671 79,696
1972 13,074 78.5% 18,842 52,504 80,414
1971 5,896 77.2% 20,098 56,944 80,134
1970 898 79.3% 21,309 57,238 76,943

How Long Does a Triumph Stag Last?

Based on 6,070 Triumph Stag vehicles on UK roads.

Average
43.0 years
Median
44.0 years
Estimated max lifespan
56 years

Triumph Stag Mileage Distribution

Total mileage recorded across all Triumph Stag MOT tests. If the car you're looking at is above the 75th percentile, it's done more miles than most.

Median
56,548 mi
75th Percentile
79,261 mi
95th Percentile
95,930 mi
Max Recorded
995,864 mi

Best Year to Buy a Used Triumph Stag

Based on MOT pass rates across all registration years with sufficient test data.

Best year
1994

88.5% MOT pass rate from 52 tests

Year to avoid
1995

71.4% MOT pass rate from 56 tests

The best year to buy a used Triumph Stag is 1994, which has the highest MOT pass rate at 88.5% across 52 tests. The 1995 model year has the lowest pass rate at 71.4% — if you're looking at one from that year, budget for potential repairs and get a thorough pre-purchase inspection.

How Does the Triumph Stag Compare?

MOT pass rates compared to similar models. Click any model for the full breakdown.

Model Pass Rate Tests Typical Mileage Lifespan
Triumph Stag THIS CAR 77.5% 64,590 56,548 mi 56 yrs
Triumph Bonneville 90.1% 235,206 7,823 mi 53 yrs
Triumph Tiger 90.6% 196,853 17,026 mi 32 yrs
Triumph Sprint 87.3% 158,613 21,242 mi 33 yrs
Seat Cordoba 66.1% 99,964 84,360 mi 32 yrs

Compared to the Triumph Bonneville (90.1% pass rate) and the Triumph Tiger (90.6% pass rate), the Triumph Stag trails behind on MOT reliability.

Found a Triumph Stag you like?

Run a full vehicle history check on the specific car. See finance, stolen, write-off, mileage and MOT data for that exact vehicle.

Check a specific Triumph Stag

Should you buy a used Triumph Stag?

The Triumph Stag has an overall MOT pass rate of 77.5% across 64,590 real MOT tests — comfortably above the UK average, which puts it among the more reliable models on UK roads.

The most common problems on the Triumph Stag are windscreen washer provides insufficient washer liquid (2,039 recorded failures), parking brake: efficiency below requirements (1,744), and suspension component mounting prescribed area is excessively corroded (1,507). These are the faults most likely to cause an MOT failure on this model, so check for them carefully on any test drive or pre-purchase inspection. Many are wear-and-tear items that can be budgeted for, but a car that's already failing on multiple fronts may signal neglected maintenance.

A typical Triumph Stag owner drives around 417 miles per year. If the car you're looking at is significantly above this, expect more wear on suspension, brakes and tyres. If it's well below, the vehicle may have been sitting unused — check for perished rubber, corroded discs and stale fluids.

In terms of longevity, most Triumph Stag models stay on UK roads for around 56 years — a strong showing that suggests solid build quality and readily available parts. If you're buying one that's already approaching that window, the data suggests it has plenty of life left provided it's been maintained.

Before committing to a purchase, we recommend running a full vehicle history check on the specific car. This will reveal any outstanding finance, stolen markers, write-off history and mileage discrepancies that the seller may not disclose — and that the MOT data alone can't tell you.

Triumph Stag — Frequently Asked Questions

Is the Triumph Stag reliable?
Based on 64,590 MOT tests, the Triumph Stag has a 77.5% pass rate — above the UK average, suggesting good reliability.
What are the common problems on a Triumph Stag?
The most common MOT failures are windscreen washer provides insufficient washer liquid, parking brake: efficiency below requirements, and suspension component mounting prescribed area is excessively corroded. Check these on any test drive.
How many miles does a Triumph Stag do per year?
The typical Triumph Stag does around 417 miles per year. Anything significantly above or below this is worth investigating.
How long does a Triumph Stag last?
Most Triumph Stag models stay on UK roads for around 56 years based on our analysis of 6,070 vehicles.
Should I get a vehicle check before buying a Triumph Stag?
Yes. An MOT pass rate tells you about the model in general, but a vehicle history check reveals the specific car's finance, stolen, write-off and mileage history — things the seller may not disclose.
What is the best year to buy a Triumph Stag?
Based on MOT pass rates, the best year to buy a used Triumph Stag is 1994 with a 88.5% pass rate across 52 tests.