Triumph Tr 7 MOT Failures

An analysis of 4,953 real DVSA MOT tests on the Triumph Tr 7 — what fails, how often, and how that compares to every other car on UK roads. Generations covered: TR7 (1975–1981).

Where the Triumph Tr 7 fails its MOT

The single biggest MOT failure point on the Triumph Tr 7 is wheel bearings worn — this model is 87 times more likely to fail on this item than the average car on UK roads. That makes it a major concern for anyone buying or owning this model. Across 4,953 MOT tests, 10.06% of all Triumph Tr 7 tests recorded this as a failure.

Suspension failures typically mean worn bushes, drop links, or dampers. These affect handling and tyre wear. Budget £150–£400 per corner at an independent garage for full suspension overhaul.

Other notable weak points include emissions failure (739x the fleet average), abs fault (18x the fleet average), track rod ends worn (140x the fleet average), and fluid leak (14x the fleet average). These ratios compare the Triumph Tr 7's failure rate on each item against the national average for all cars tested — a ratio of 10x means this model fails ten times more often than a typical car.

The failures span 4 categories: Suspension, Exhaust & Emissions, Steering, Brakes. If you're inspecting a Triumph Tr 7 before purchase, these are the areas to focus on — and if any have been flagged as advisories on a previous MOT, they're likely to become failures in the near future.

How failures change with mileage

The Triumph Tr 7's weak points shift as the car covers more miles. Understanding these patterns helps you know what to expect — and what to budget for — at each stage of ownership.

Under 60,000 miles

At this mileage, most failures are either design-related or caused by age rather than wear. Components like bushes and drop links may not have been replaced yet, and original-fit parts can deteriorate even on low-mileage cars that spend a lot of time sitting.

For the Triumph Tr 7 specifically, the DVSA data shows the most common failures at this mileage are emissions failure (739x the average) and track rod ends worn (140x). service brake efficiency below minimum requirement (55x) and wheel bearings worn (34x) also appear frequently.

60,000 to 100,000 miles

This is where routine wear items start to show up. Brake components, tyres, and exhaust parts have done serious work by this point. Cars that have been well serviced will show fewer of these failures — this mileage band is where good maintenance really separates the well-kept from the neglected.

For the Triumph Tr 7 specifically, the DVSA data shows the most common failures at this mileage are emissions failure (342x the average) and brakes imbalance across an axle (24x). wheel bearings worn (19x) and abs fault (5.8x) also appear frequently.

Known issues beyond the MOT

An MOT only tests roadworthiness at a single point in time — it won't catch developing faults, intermittent problems, or issues that haven't yet reached the failure threshold. These are the issues that Triumph Tr 7 specialists and owners flag most frequently, drawn from manufacturer technical bulletins, workshop data, and verified owner reports.

Subframe structural corrosion (TR7) Dangerous

The TR7's front and rear subframes are known to suffer from structural corrosion that compromises the mounting points for suspension components and steering. Affects TR7; typical independent garage repair cost is £800–£1,500.

Wheel bearing failure (TR7) Major

The TR7 exhibits wheel bearing problems at 21.9 times the national fleet average according to MOT failure data, with 150 recorded failures. Affects TR7; typical independent garage repair cost is £150–£250.

Emissions system failure (TR7) Major

This reflects the difficulty of maintaining correct air-fuel mixture on the original carburettor setup as components age. Affects TR7; typical independent garage repair cost is £200–£400.

Fluid leaks from engine and transmission (TR7)

The TR7 is notorious for multiple oil and fluid seepage points including rocker cover gaskets, sump gaskets, rear main seal, and transmission seals. Affects TR7; typical independent garage repair cost is £100–£300.

For the complete picture — including repair costs across independent, specialist, and dealer garages — see the full Triumph Tr 7 common problems breakdown.

What to check before buying a Triumph Tr 7

Based on the MOT failure data and known issues above, here's what to prioritise when inspecting a Triumph Tr 7:

Suspension — check for wheel bearings worn, abs fault, suspension joint dust cover severely deteriorated. Exhaust & Emissions — check for emissions failure, fluid leak. Steering — check for track rod ends worn.

Beyond the MOT items, ask specifically about subframe structural corrosion and wheel bearing failure. These won't show up on a standard MOT but can be expensive to fix — repairs start from £800. A specialist pre-purchase inspection is worth the investment on this model.

Always check the car's full MOT history for patterns — recurring advisories often become failures within 12 months. And verify the service history to confirm maintenance has been kept up to schedule. Enter any reg into our free car check to see the complete picture.

MOT failure data sourced from DVSA bulk test records via data.gov.uk. Ratios compare this model's failure rate against the national fleet average. Known issues sourced from manufacturer bulletins, specialist workshops, and verified owner reports.