Common problems

London Taxis International TX4 common problems

What MOT testers find on the London Taxis International TX4: the parts that fail or get advisories most often at each age, against all cars of the same age. From 53,539 DVSA MOT tests taken 2022 to 2025.

MOT data updated 28 September 2026

At 9 years, the most tested age

Lights and electrics fails per 100 MOTs (n=7,223)17.7

All cars at 9 years (n=9,949,012)9.2

Suspension advisories and minor defects per 100 MOTs (n=7,223)23.9

All cars, same age (n=9,949,012)14.9

What stands out

Suspension fails show up on 16.7 of every 100 MOTs of a London Taxis International TX4 at 9 years old (n=7,223), against 7.9 for all cars of that age (n=9,949,012).
Tyres fails are less common: 4.3 per 100 MOTs against 6.7 for all cars at the same age.
The fail item testers record most often at 9 years: suspension arm bush worn, on 6.7 per 100 MOTs (all cars 1.1).
The most common advisory or minor defect: engine oil leaks: leak, but not excessive, on 11.1 per 100 MOTs.

Problems by part at 9 years

How many of every 100 MOTs found a fail, or an advisory or minor defect, in each area. A test with faults in two areas counts in both.

London Taxis International TX4 at 9 years (n=7,223) against all cars at 9 years (n=9,949,012). Per 100 MOTs.
Area	Fails	All cars	Advisories	All cars
Lights and electrics	17.7	9.2	6.5	4.5
Suspension	16.7	7.9	23.9	14.9
Brakes	9.2	5.6	13.5	20.3
Exhaust, emissions and leaks	7.0	2.4	13.8	3.1
Windscreen, wipers and mirrors	5.5	4.0	3.9	3.7
Tyres	4.3	6.7	10.9	25.8
Steering	3.6	1.8	8.0	2.1
Body and structure	3.0	2.3	1.9	2.9
Seat belts and airbags	0.7	0.6	0.1	0.4
Road wheels	0.3	0.4	under 0.1	0.7
Number plates and VIN	0.1	0.3	0.5	1.7

What testers fail most on the TX4 at 9 years

Fail items on the London Taxis International TX4 at 9 years (n=7,223), per 100 MOTs, with all cars at the same age (n=9,949,012).
Item	Area	Per 100 MOTs	All cars	Typical repair (estimate)
Suspension arm bush worn	Suspension	6.7	1.1	£92 to £237 per arm (rough guide)
Side/position light not working	Lights and electrics	4.0	1.7	£10 to £47 per lamp
Malfunction indicator lamp: inoperative or indicates a malfunction	Exhaust, emissions and leaks	3.6	0.6	diagnosis from £39 (rough guide)
Suspension ball joint worn	Suspension	3.1	1.5	£75 to £237 per side (rough guide)
Handbrake too weak	Brakes	2.9	0.7
Dipped headlight not working	Lights and electrics	2.8	1.5	£18 to £86 per lamp
Tyre tread below 1.6 mm	Tyres	2.8	2.5	£88 to £145 per tyre
Coil spring broken	Suspension	2.4	2.7	£64 to £236 per spring (rough guide)
Registration plate lamp(s): inoperative in the case of a single lamp or all lamps	Lights and electrics	2.2	1.0	£10 to £47 per lamp
Washers: provides insufficient washer liquid	Windscreen, wipers and mirrors	2.1	1.3	£2 to £14 per car (rough guide)

Early warnings: advisories and minor defects at 9 years

Advisories and minor defects are recorded, but the car still passes. Across all cars, a part with an advisory or minor defect failed at the next MOT 5.5 times in 100 (n=88,666,940 pairs of consecutive MOTs), against 0.3 times in 100 when the same part had none (n=12,936,860,350).

Advisories and minor defects on the London Taxis International TX4 at 9 years (n=7,223), per 100 MOTs, with all cars at the same age (n=9,949,012).
Item	Area	Per 100 MOTs	All cars	If it needs replacing (estimate)
Engine oil leaks: leak, but not excessive	Exhaust, emissions and leaks	11.1	2.5
Suspension arm pins and bushes: pin or bush worn but not resulting in excessive movement	Suspension	10.6	4.9	£92 to £237 per arm (rough guide)
Tread depth: worn close to legal limit/worn on edge	Tyres	8.5	16.4	£88 to £145 per tyre
Wheel bearings: has slight play	Suspension	4.2	0.3	£103 to £276 per wheel (rough guide)
Steering box: has seepage	Steering	4.1	under 0.1
Brake discs: worn, pitted or scored, but not seriously weakened	Brakes	3.7	9.2	£148 to £376 per axle (rough guide)
Rigid brake pipes: corroded, covered in grease or other material	Brakes	3.6	2.1	£137 to £392 per car (rough guide)
Shock absorbers: has a slightly worn bush	Suspension	3.5	0.3	£122 to £484 per axle (pair) (rough guide)
Brake pads: wearing thin	Brakes	3.5	8.3	£72 to £174 per axle (rough guide)
Coil spring: corroded	Suspension	3.5	2.0

Repair estimates are a guide for an independent garage: labour at the national median local garage rate (median £78 an hour from 65 garages, ONS price quotes) times estimated labour hours, plus a parts band. Labour hours and most parts bands are estimates, not quotes, and prices vary by model, engine and region. A warning light fault shows the cost of the diagnosis only.

How problems change with age

Fails per 100 MOTs in the three most common areas at 9 years. Ages with fewer than 1,000 tests are not shown.
Age	Tests (n)	Lights and electrics	Suspension	Brakes
5 years	1,072	13.9	14.0	7.9
6 years	2,704	13.5	14.5	7.7
7 years	4,816	14.4	14.3	7.6
8 years	7,039	16.3	16.1	8.9
9 years	7,223	17.7	16.7	9.2
10 years	7,036	17.6	16.0	10.1
11 years	7,002	18.5	15.9	10.8
12 years	4,858	16.8	17.3	12.8
13 years	4,047	16.6	19.2	14.0
14 years	3,353	17.0	18.5	14.9
15 years	2,775	18.3	18.5	18.1
16 years	1,614	18.7	16.7	14.9

What to check on a viewing

On the London Taxis International TX4, testers most often record suspension arm bush worn; side/position light not working; malfunction indicator lamp: inoperative or indicates a malfunction. Look at these first, then the areas below.

Lights and electrics

With someone outside, try every light: dipped and main beam, indicators, brake lights, fog lights and number plate lamps.
Check that the warning lights come on with the ignition and go out once the engine runs.
Look for misted, cracked or yellowed headlamp lenses.

Suspension

Listen for knocks or clonks over speed bumps and rough roads on the test drive.
Push down hard on each corner: the car should settle at once rather than keep bouncing.
Look behind the wheels for broken or heavily rusted coil springs and split rubber bushes.
Check that the car sits level and that no tyre is worn on one edge only.

Brakes

On the test drive the car should stop in a straight line without pulling, juddering or grinding.
Look at the discs through the wheels for a deep lip, heavy rust or scoring.
Check that the handbrake or electronic parking brake holds the car on a slope.
Ask when the pads, discs and brake fluid were last changed, and for the receipts.

Ask for the car's MOT history and service record: advisories that repeat from one year to the next show what has been left. GOV.UK MOT history.

Questions

What are the most common problems on the London Taxis International TX4?

At 9 years, the age with the most MOT tests (7,223), the fail items testers record most often on the London Taxis International TX4 are suspension arm bush worn (6.7 per 100 MOTs), side/position light not working (4.0 per 100 MOTs), malfunction indicator lamp: inoperative or indicates a malfunction (3.6 per 100 MOTs). The most common advisories or minor defects are engine oil leaks: leak, but not excessive (11.1) and suspension arm pins and bushes: pin or bush worn but not resulting in excessive movement (10.6).

Which parts of the London Taxis International TX4 fail more often than on other cars?

At 9 years: suspension (16.7 per 100 MOTs against 7.9 for all cars); lights and electrics (17.7 per 100 MOTs against 9.2 for all cars); exhaust, emissions and leaks (7.0 per 100 MOTs against 2.4 for all cars). Compared with 9,949,012 MOTs of all cars the same age.

London Taxis International TX4 problems by area

Other London Taxis International models

All London Taxis International models · Common problems by make

Read this with care. A fail rate is not a measure of build quality. How far cars are driven, how they are used and how well owners maintain them all change it, and wear items such as tyres and brake pads are common fails. Compare a model only with cars of the same age. Methodology and limits.

The all cars figures cover all class 4 vehicles (cars and light vans) tested at the same age.

Looking at a London Taxis International TX4?

These figures describe the model, not the car in front of you. Found one you might buy? See what the VetTheCar Buying Report covers, or use the tools that work without a registration.

See a sample report Car tools · MOT fail rates by model · Compare models by MOT record

Repair estimates: ONS consumer price quotes for local garage labour (09/2025 to 08/2026), the MOT inspection manual for defect wording, and estimated labour hours and parts bands. Not affiliated with or endorsed by ONS.

Source

Contains public sector information licensed under the Open Government Licence v3.0. Source: DVSA anonymised MOT test data, class 4 normal MOT tests, 2022 to 2025. MOT data updated 28 September 2026.

Not affiliated with or endorsed by DVSA. How we calculate these figures · Data sources