BMW 4 Series: Best Years and Years to Avoid
The 4 Series is essentially the 3 Series coupe and convertible, so it shares the same engines and the same engine-specific risks. There are only two generations: the F32 and the current G22. Neither is a blanket avoid, but the early F32 timing-chain engines need the same scrutiny they do in the 3 Series.
Quick answer
Best all-round pick: a G22 420i/430i or 420d, or a post-2015 F32 with the B-series engines. Be most careful with pre-2015 N20 petrols and early N47 diesels. The 435i/440i (N55/B58) are the enthusiast picks and generally robust.
G22 / G23 / G26 (2020-present) Buy
Chassis: G22, G23, G26
The current 4 Series is the safe used choice, built on BMW's modular B-series engines and sharing the well-sorted G20 3 Series platform. Faults so far are minor and mostly electronic. The 440i and M440i (B58) are strong, dependable straight sixes.
| Best years | Any G22 420i, 430i or 420d with full history is a reasonable buy. The 440i/M440i are the enthusiast choices. |
| Years to watch | Very early 2020 cars may have had software updates; check infotainment and driver aids work fully. Divisive front-grille styling aside, there are no major mechanical concerns. |
| Engines to trust | 420i (B48), 430i (B48), 420d (B47), 440i (B58), M440i (B58) |
| Engines to check | Early cars with outstanding software updates |
Key risks
- Occasional infotainment and software glitches on early cars
- B47 diesel DPF regeneration needs; avoid short-trip-only cars
- Verify the electric folding roof operation on G23 convertibles
F32 / F33 / F36 (2013-2020) Mixed
Chassis: F32, F33, F36
The first 4 Series, and mechanically an F30 3 Series in coupe, convertible or Gran Coupe form. Quality depends on the engine and year: later facelift cars with B-series engines are the ones to target, while early N20 petrols and N47 diesels need the same chain scrutiny as the equivalent 3 Series.
| Best years | 2015-2020 LCI cars with the B48 petrol or B47 diesel, or the well-regarded B58-powered 440i, are the durable choices. |
| Years to watch | 2013-2015 420i/428i (N20) for timing-chain stretch and 420d (N47) for the rear chain. |
| Engines to trust | 440i (B58), 430i (B48), 420d (B47, later), 435i (N55), 428i (N20, post-2015) |
| Engines to check | 420i / 428i pre-2015 (N20 timing chain), 418d / 420d (N47 timing chain), 435i (N55, minor) |
Key risks
- N20 timing-chain stretch on pre-2015 petrols; listen for extended cold-start rattle
- N47 diesel rear timing chain, expensive to replace
- Diesel DPF and EGR issues on short-trip cars
- N55 (435i): water pump, oil filter housing gasket and VANOS solenoids are known wear items
The pick of the range
For most buyers, a 2015-2020 F32 420d (B47) or 430i (B48) with full service history is the value sweet spot: 3 Series mechanicals with coupe or convertible style and modern reliable engines. If budget allows, a G22 of the same badges is the safer long-term choice. Enthusiasts should target a 440i (B58), one of BMW's most dependable modern straight sixes.
What to avoid, and why
Be most cautious with pre-2015 F32 420i/428i cars (N20 timing chain) and any N47 diesel (418d/420d) without documented chain replacement, exactly as with the equivalent F30 3 Series. On the 435i (N55), factor in water pump and VANOS wear. None are automatic walk-aways, but each needs receipts before you commit.
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Get your report →Bimmer.AI is designed to help you identify BMW-specific buyer risks before you travel, negotiate, or pay for an inspection. It does not replace a physical inspection by a qualified mechanic, a legal vehicle-history check (e.g. HPI Check), or independent verification of finance, stolen, or write-off status. Repair-cost ranges are indicative UK figures that vary by region, specialist, parts supply, and labour rates.
Frequently asked questions
What is the most reliable BMW 4 Series year?
The current G22 generation (2020 on) is the most reliable, using BMW's modular B48 and B58 engines. Among older cars, a post-2015 F32 with a B48 petrol or B47 diesel is the durable value choice.
Which BMW 4 Series should I avoid?
No generation is a blanket avoid. Be most careful with pre-2015 F32 420i/428i cars (N20 timing chain) and any N47 diesel without chain-replacement receipts. Both need documented evidence before you buy.
Is the F32 4 Series reliable?
It shares the F30 3 Series mechanicals, so it depends on the engine and year. Post-2015 cars with B48/B47/B58 engines are reliable; early N20 petrols and N47 diesels are fine once the timing chain has been sorted.
Is the BMW 435i or 440i a good buy?
Yes. The 435i (N55) is a smooth, relatively robust turbo six, needing only routine attention to its water pump and VANOS solenoids. The 440i (B58) is one of BMW's most dependable modern engines and the pick of the range.
Petrol or diesel 4 Series for the UK?
For higher mileage, a post-2015 B47 diesel (420d) is efficient and durable. For lower mileage or a sportier feel, a B48 petrol (430i) or a straight-six 435i/440i avoids DPF and EGR concerns. Older N47 diesels carry timing-chain risk that later engines resolved.
Does the BMW 4 Series have timing chain problems?
Only on the early F32 engines: the pre-2015 N20 petrol and the N47 diesel, the same units used in the F30 3 Series. Later B-series engines are far more robust. Check for chain history on the affected engines.