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Triumph Stag reliability by build year

Coverage 1970-19771 named generationConvertiblePETROL

We've only got 1,436 MOT tests for Triumph Stags built before 2000 (over 25 years old). Treat these numbers as a rough guide.

At a glance

Triumph Stag built before 2000: fails its MOT less often than average

Triumph Stags built before 2000 fail their MOT less often than similar cars the same age. An independent inspection matters more than the wider numbers on cars this old.

Check a Triumph Stag by number plate

Key figure

16% of MOT tests on Triumph Stags built before 2000 ended in a fail (retests included), against 22% for similar cars the same age.

Most common issue

The most common MOT issue on Triumph Stags built before 2000 involves fluid leaks.

Before you view it

What to check before viewing

The Triumph Stag's most common MOT issues, turned into things to ask about or look for.

Leaks

Worth checking

Inspect the leaks carefully and ask the seller for repair history.

Axles & Wheels

Worth checking

Inspect the axles & wheels carefully and ask the seller for repair history.

Suspension bushes and joints

Worth checking

Listen for knocks over speed bumps and ask about recent control-arm or anti-roll-bar work.

Steering

Worth checking

Inspect the steering carefully and ask the seller for repair history.

Suspension

Worth checking

Inspect the suspension carefully and ask the seller for repair history.

Vehicle-specific check

Worth checking

Check the car’s number plate on MOT Wise to see its own MOT history and any recalls for its build years.

By build year

How build years differ

Fail rates have been steady over the last three years. Use the build-year guide below to separate newer build years from older ones.

Find your Stag's generation

Each card below is a different generation. Select your year and we'll highlight the match.

Stag Mk1/Mk2

Mk1/Mk2 (1970-1977)

Excellent
PETROL

15.7% fail rate, built before 2000 (over 25 years old)

Fails less often than the average car this age (about 1 in 4 MOTs, 25.2%)

From 1,436 MOT tests at this ageView details →

By age

Triumph Stag fail rate by age

This chart combines every Triumph Stag ever sold. It's good for the big picture. For one generation, scroll up to the build-year cards.

Below typicalAbove typicalHigh (28% or more)Highest fail rate
Age / builtFail rateMOT tests
25+ yearsbuilt 2000 or earlier
1,43615.7%

Fail rate is the share of MOT tests that ended in a fail. Retests count as tests. How we count fail rates Build years are worked out from age, so they are approximate. Tests counted are 2025 MOTs. Highest fail rate at 25+ years old.

All generations of this model

What goes wrong most often on 25+ year old Triumph Stags

These issues come from 25+ year old Triumph Stags, every generation combined.

All generations of this modelEnough data

Most common advisories and fails

In order of the share of MOT tests that recorded each one

  1. 1
    Advisory

    Oil leak, but not excessive

    17.8%
    Advisory: 319Fail: 10 (3% of the times it was found)
  2. 2
    Advisory

    Wheel bearing has slight play

    10.0%
    Advisory: 188Fail: 13 (6% of the times it was found)
  3. 3
    Advisory

    Suspension arm pin or bush worn, but not moving too much

    7.8%
    Advisory: 154Fail: 28 (15% of the times it was found)
  4. 4
    Advisory

    Power steering has a slight leak

    3.8%
    Advisory: 49Fail: 7 (13% of the times it was found)
  5. 5
    Advisory

    Exhaust has a minor leak

    3.3%
    Advisory: 46Fail: 3 (6% of the times it was found)

Based on 1,436 MOT tests on 25+ year old Triumph Stags, every generation combined.

All generations of this model

Issues that often appear together

The pairs seen most often when an MOT on 25+ year old Triumph Stags notes problems with more than one part of the car.

Issues that often appear together on this model

All generations of this modelEnough data
  1. Other + Suspension24%
  2. Fuel & oil + Other24%
  3. Fuel & oil + Suspension21%
  4. Fuel & oil + Steering21%

Both were noted at the same test. That doesn't mean one caused the other.

Across 401 MOT tests on Triumph Stag cars built before 2000 (over 25 years old) where more than one part of the car was noted.

Still registered

How many are still registered, and recalls

How many of these are still registered in the UK, and what's been recalled across the model.

How many are still registered

Not enough registration data to show this for the Triumph Stag.

The share still registered can reflect demand, the cost of repairs, exports, write-offs and how owners use the car. It isn't proof of how long the car lasts mechanically.

Recall context

DVSA's recall list has no recalls filed under the Triumph Stag name. For the exact car, check with the maker or GOV.UK's recall checker.

Like-for-like

Other convertibles to compare

Other convertibles to compare

  1. 1

    Mercedes-Benz SL

    Same body type, tested at the same age

    Fail rate
    17.1%
    Still registered at 10 years
    90.5%

    No clear edge over the Triumph Stag on these figures.

    Some figures could not be compared for these two cars. So this comparison uses the fail rate and recalls only.

    5,842 MOT tests on cars built before 2000

  2. 2

    MG B

    Same body type, tested at the same age

    Fail rate
    15.5%

    No clear edge over the Triumph Stag on these figures.

    Some figures could not be compared for these two cars. So this comparison uses the fail rate and recalls only.

    2,865 MOT tests on cars built before 2000

  3. 3

    Mazda MX-5

    Same body type, tested at the same age

    Fail rate
    27.2%
    Still registered at 10 years
    97.6%

    No clear edge over the Triumph Stag on these figures.

    2 critical recall campaigns matching this model/build period.

    16,460 MOT tests on cars built before 2000

  4. 4

    Lotus Elise

    Same body type, tested at the same age

    Fail rate
    14.8%

    No clear edge over the Triumph Stag on these figures.

    2 critical recall campaigns matching this model/build period.

    2,026 MOT tests on cars built before 2000

Fail rate
= the share of MOT tests that ended in a fail. Retests count as tests.
Still registered at 10 years
= the share of cars still registered (taxed or declared off the road) 10 years after they were first registered.

Common questions

Frequently asked questions

Built before 2000 (over 25 years old), the Triumph Stag across all generations combined fails MOTs noticeably less often than typical for this age. This is based on 1,436 25+ year old MOT tests from DVSA data. Each retest counts as a test.

These figures come from DVSA's MOT records. Across every Triumph Stag ever sold: 1,436 tests. The main figures are for cars built before 2000 (over 25 years old): 1,436 tests. They are a guide, not a guarantee. Always inspect the car or have a mechanic check it.