Jaguar 420 Reliability, MOT Pass Rate & Common Faults
Free Jaguar 420 car check
Is the Jaguar 420 reliable? We analysed 2,524 real MOT tests across 323 vehicles to find out.
Got a specific Jaguar 420? Enter the reg for a free check:
The Jaguar 420 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 headlamp not working on main beam. Here's everything you need to know before buying a used Jaguar 420.
Jaguar 420 Number Plates
Number plates registered to a Jaguar 420. Click on any registration for full vehicle details — including MOT history, mileage records, previous owners and damage history.
Jaguar 420 MOT Pass Rate by Year
How likely is a Jaguar 420 to pass its MOT? Here's the pass rate for each registration year, newest first.
Jaguar 420 Problems — What Goes Wrong?
The most common reasons a Jaguar 420 fails its MOT, ranked by how often they occur. Check for these problems before you buy.
Jaguar 420 Mileage — What's Normal?
How many miles does a typical Jaguar 420 owner drive per year? Use this to check if a car you're looking at has suspiciously low or high mileage.
Jaguar 420 MOT Data by Registration Year
Full breakdown of pass rate and mileage for each year. Use this to compare the Jaguar 420 year you're looking at.
| Year | Tests | Pass Rate | Low Mi. | Typical Mi. | High Mi. |
|---|---|---|---|---|---|
| 1970 | 170 | 81.2% | 18,522 | 38,777 | 76,652 |
| 1969 | 123 | 80.5% | 29,553 | 41,350 | 83,742 |
| 1968 | 969 | 78.8% | 17,684 | 46,928 | 76,335 |
| 1967 | 847 | 79.7% | 24,548 | 60,148 | 72,527 |
How Long Does a Jaguar 420 Last?
Based on 323 Jaguar 420 vehicles on UK roads.
Jaguar 420 Mileage Distribution
Total mileage recorded across all Jaguar 420 MOT tests. If the car you're looking at is above the 75th percentile, it's done more miles than most.
Best Year to Buy a Used Jaguar 420
Based on MOT pass rates across all registration years with sufficient test data.
81.2% MOT pass rate from 170 tests
78.8% MOT pass rate from 969 tests
The best year to buy a used Jaguar 420 is 1970, which has the highest MOT pass rate at 81.2% across 170 tests. The 1968 model year has the lowest pass rate at 78.8% — if you're looking at one from that year, budget for potential repairs and get a thorough pre-purchase inspection.
How Does the Jaguar 420 Compare?
MOT pass rates compared to similar models. Click any model for the full breakdown.
| Model | Pass Rate | Tests | Typical Mileage | Lifespan |
|---|---|---|---|---|
| Jaguar 420 THIS CAR | 80.2% | 2,524 | 53,559 mi | 59 yrs |
| Jaguar X-type | 73.4% | 1,912,556 | 80,596 mi | 25 yrs |
| Jaguar Xf | 80.8% | 1,374,522 | 65,620 mi | 18 yrs |
| Jaguar S-type | 74.5% | 942,176 | 77,805 mi | 27 yrs |
| Kawasaki Zr 750 L9F | 85.2% | 2,227 | 12,685 mi | 18 yrs |
Compared to the Jaguar X-type (73.4% pass rate) and the Jaguar Xf (80.8% pass rate), the Jaguar 420 sits in the middle of the pack on MOT reliability.
Found a Jaguar 420 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 Jaguar 420Should you buy a used Jaguar 420?
The Jaguar 420 has an overall MOT pass rate of 80.2% across 2,524 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 Jaguar 420 are windscreen washer provides insufficient washer liquid (101 recorded failures), parking brake: efficiency below requirements (73), and headlamp not working on main beam (57). 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 Jaguar 420 owner drives around 308 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 Jaguar 420 models stay on UK roads for around 59 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.