BMW S58B30 engine code explained
S58B30 is the full code for the current M Division straight-six, launched in the F97 X3 M and F98 X4 M in 2019 and then fitted to the G80 M3, G82 / G83 M4 and G87 M2. Derived from the B58 rather than the S55, it has a closed-deck block, a forged crank, two mono-scroll turbos and, on the later S58TU, port injection alongside direct injection. Outputs run from 454 to 543 bhp on what is essentially one engine code.
Quick answer
The S58B30 is the 3.0-litre straight-six twin-turbo M engine petrol of the BMW S58 family, built 2019-present. Bimmer.AI scores the family 8 / 10: one of the safest used BMW engines to buy. The tables below give every output tier and sticker letter BMW used on this stem and which cars got them; the failure table is the same one that powers the S58 family guide.
How to read S58B30
| Part of the code | Meaning |
|---|---|
| S | BMW M GmbH (M Division) engine |
| 58 | engine family number within the S-series |
| B | petrol, longitudinal (rear-drive platform: 1 to 8 Series, X3 to X7, Z4) |
| 30 | displacement in tenths of a litre: 3.0 litres |
| K / U / M / O / T / S + digit | output tier and revision, appended in BMW's internal naming (for example S58B30O1) |
| A / B / C / D | parts-catalogue engine version printed on the engine cover sticker (for example S58B30A) |
S58B30 output tiers and which cars have them
| Code | Output | Cars | Notes |
|---|---|---|---|
| S58B30T0 | 473 bhp (M3 / M4 manual), 503 bhp (Competition), 454 bhp (M2), 523 bhp (M3 CS, M2 CS), 543 bhp (M4 CSL) | X3 M / X4 M (F97 / F98 2019-2024), M3 (G80 / G81 2021 on), M4 (G82 / G83 2021 on), M2 (G87 2023 on), M4 CSL (2023), M3 CS, M2 CS | One code, many tunes; S58TU from 2022 adds port injection |
S58B30 sticker letters: S58B30A, S58B30B
Most parts catalogues list every S58 application under S58B30T0 and separate them by letter and software. The buyer-relevant split is the TU: a B-letter car has port injection and therefore a much smaller carbon-build-up conversation. Most S58 cars are still inside the BMW warranty, so the Phase 1 checks are the plastic charge pipes, the oil-filter-housing gasket and the water pump.
| Sticker code | What it denotes |
|---|---|
| S58B30A | Original S58 (2019 to 2022). |
| S58B30B | S58TU (2022 onwards): added port injection, which reduces intake-valve carbon build-up. |
Known problems on every S58B30
Failure data is held once, per engine family, so this table is identical to the BMW S58 guide. Cost ranges are indicative UK figures.
| Failure mode | Severity | Frequency | Typical onset | UK repair range |
|---|---|---|---|---|
| OEM plastic charge pipe (carried over from B58 / S55 pattern) | Moderate | Uncommon | 40 to 100k mi | £150 to £400 |
| Oil filter housing gasket leak | Moderate | Uncommon | 70 to 130k mi | £220 to £480 |
| Intake valve carbon buildup | Moderate | Uncommon | 60 to 120k mi | £400 to £700 |
| Electric water pump failure | Moderate | Uncommon | 60 to 130k mi | £500 to £750 |
Long-term verdict
Phase 1 record. The S58 is BMW's current M-engine and is still under 7 years old. Early signals are positive: closed-deck block, B58-derived architecture (which is well-proven), no catastrophic systemic failures documented in the UK market to date. The OEM plastic charge pipe is the same documented weak point as B58 / N55 / S55 and is the standard early aftermarket upgrade. Long-term picture will sharpen materially as the fleet ages over 2026 to 2028.
Check a specific S58B30 listing
Paste any BMW S58 listing, VIN or registration. Bimmer.AI identifies the exact engine and returns the buyer report in 30 seconds.
Run a Bimmer.AI buyer 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
Does the S58B30 need rod bearings like the S55?
Not so far. The S58 uses a different bearing specification and clearance philosophy, and there is no documented pattern of rod-bearing wear on the engine as there was on the S55 and S65. Given how young the fleet is, treat that as encouraging rather than proven, and keep oil changes at 5,000 to 7,000 miles on any tracked car.
Which S58B30 is the strongest?
The M4 CSL at 543 bhp, then the M3 CS and M2 CS at 523 bhp, the Competition cars at 503 bhp, the manual M3 / M4 at 473 bhp and the M2 at 454 bhp. All are the same S58B30T0 hardware with different boost, cooling and software; the CSL and CS add a higher boost limit and stiffer engine mounts. Reliability is identical across the range.
Which BMWs have the S58B30 engine?
The S58B30 went into the following cars, by output tier. S58B30T0 (473 bhp (M3 / M4 manual), 503 bhp (Competition), 454 bhp (M2), 523 bhp (M3 CS, M2 CS), 543 bhp (M4 CSL)): X3 M / X4 M (F97 / F98 2019-2024), M3 (G80 / G81 2021 on), M4 (G82 / G83 2021 on), M2 (G87 2023 on), M4 CSL (2023), M3 CS, M2 CS. The two-letter family badge is S58; any listing that quotes the family code is talking about one of these.
Is the BMW S58B30 reliable?
Bimmer.AI scores the S58 family 8 out of 10, which makes the S58B30 one of the safest used BMW engines to buy. Phase 1 record. The S58 is BMW's current M-engine and is still under 7 years old. Early signals are positive: closed-deck block, B58-derived architecture (which is well-proven), no catastrophic systemic failures documented in the UK market to date. The OEM plastic charge pipe is the same documented weak point as B58 / N55 / S55 and is the standard early aftermarket upgrade. Long-term picture will sharpen materially as the fleet ages over 2026 to 2028.
What does S58B30 mean?
S is the BMW M GmbH (M Division) engine, 58 is the family number, B means petrol, longitudinal (rear-drive platform: 1 to 8 Series, X3 to X7, Z4), and 30 is the displacement in tenths of a litre (3.0 litres). BMW appends an output tier and revision (K, U, M, O, T or S plus a digit) in its own naming, and the parts catalogue adds a version letter (A, B, C) that is what you see on the engine cover.