BMW N57D30 engine code explained
N57D30 is the full code for BMW's 3.0-litre straight-six diesel of 2008 to 2017: the 325d, 330d, 525d, 530d, 535d, 730d, 740d, X3 30d, X5 30d and 40d. It was built in single-turbo, twin-turbo and tri-turbo form, and the suffix tells you which. The single-turbo 258 bhp N57D30O1 in a 330d or 530d is one of the best diesels BMW ever made; the tri-turbo N57D30S1 in the M550d and M50d is the one with the actuator reputation. The 535d and 40d are twin-turbo, not tri-turbo, despite what many listings say.
Quick answer
The N57D30 is the 3.0-litre straight-six diesel of the BMW N57 family, built 2008-2017. Bimmer.AI scores the family 7 / 10: a strong used buy with a short list of known preventatives. 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 N57 family guide.
How to read N57D30
| Part of the code | Meaning |
|---|---|
| N | N-series engine generation (2001 to about 2015) |
| 57 | engine family number within the N-series |
| D | diesel, longitudinal (rear-drive platform) |
| 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 N57D30O1) |
| A / B / C / D | parts-catalogue engine version printed on the engine cover sticker (for example N57D30A) |
N57D30 output tiers and which cars have them
| Code | Output | Cars | Notes |
|---|---|---|---|
| N57D30U0 | 204 bhp, single turbo | 325d (E90 / E91 / E92 2010-2013), 525d six-cylinder (F10 2010-2011) | Detuned entry six |
| N57D30O0 | 245 bhp, single turbo | 330d (E90 2008-2012), 530d (F10 2010-2011), 730d (F01 2008-2012), X5 xDrive30d (E70 2008-2010), X6 30d | Original N57 |
| N57D30O1 | 258 bhp, single turbo (N57N) | 330d (F30 / F31 2012-2019), 430d, 530d (F10 / F11 2011-2017), 630d, 730d LCI, X3 xDrive30d (F25), X5 xDrive30d (F15 2013-2018), X6 30d | The volume tier; Euro 6 on 2014-onwards builds |
| N57D30T0 | 299 then 313 bhp, twin-turbo | 535d (F10 / F11 2010-2017), 640d, 740d (F01), X5 xDrive40d (E70 2010-2013, F15 2013-2018), X6 40d, X3 xDrive35d (F25, mostly US) | Two-stage turbo; NOT the tri-turbo |
| N57D30T1 | 313 bhp, twin-turbo (Euro 6) | 335d xDrive (F30 / F31 2013-2019), 435d xDrive (F32 / F33 / F36), X5 xDrive40d LCI (F15 2016-2018) | Euro 6 twin-turbo |
| N57D30S1 | 381 bhp, tri-turbo (N57S) | M550d xDrive (F10 / F11 2012-2017), X5 M50d (E70 2012-2013, F15 2013-2018), X6 M50d (E71 / F16), 750d xDrive (F01 2012-2015) | The only tri-turbo; documented actuator failures past 100k |
N57D30 sticker letters: N57D30A, N57D30B, N57D30C
The parts-catalogue letters roughly track the turbo count on the N57, which is the thing that actually matters to a buyer: A single, B twin, C triple. Treat the letter as a hint and confirm with the badge. Any 30d or 25d is single-turbo, any 35d, 40d or 535d is twin-turbo, and only the M550d, M50d and 750d carry the tri-turbo N57S.
| Sticker code | What it denotes |
|---|---|
| N57D30A | Original single-turbo N57 (2008 to 2011). |
| N57D30B | Twin-turbo applications (535d, 740d, 40d) in the parts catalogue. |
| N57D30C | Tri-turbo N57S (M550d, M50d, 750d). |
Known problems on every N57D30
Failure data is held once, per engine family, so this table is identical to the BMW N57 guide. Cost ranges are indicative UK figures.
| Failure mode | Severity | Frequency | Typical onset | UK repair range |
|---|---|---|---|---|
| Swirl flap failure | Catastrophic | Common | 80 to 160k mi | £250 to £450 |
| Tri-turbo actuator failure (N57S: M50d / M550d / 750d only) | Serious | Very common | 60 to 120k mi | £400 to £2,500 |
| EGR cooler failure / coolant leak | Serious | Common | 80 to 150k mi | £600 to £1,200 |
| Timing chain (very late N57 with high mileage) | Moderate | Uncommon | 150 to 250k mi | £1,800 to £3,000 |
| Crankshaft position sensor failure | Mild | Common | 60 to 150k mi | £150 to £300 |
| Oil cooler / oil filter housing gasket leak | Mild | Common | 80 to 160k mi | £250 to £500 |
Long-term verdict
One of BMW's most capable diesel engines, the 530d's 3.0L straight-six is a long-distance tourer's dream: 500-mile tanks, 0-60 in under 6 seconds, real-world 45+ mpg on a run. Known for longevity (300,000+ miles with care) but the N57S tri-turbo (M550d, X5/X6 M50d and 750d only; the 535d is the twin-turbo unit) has chronic turbo actuator issues. Pre-2014 builds are Euro 5 and NOT ULEZ compliant, major issue for London buyers. With service history and known weak points addressed, one of the best all-round BMW powerplants ever made.
Check a specific N57D30 listing
Paste any BMW N57 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
Is the 535d an N57D30S1 tri-turbo?
No. The 535d (F10 / F11, 2010 to 2017) uses the twin-turbo N57D30T0 at 299 to 313 bhp. The tri-turbo N57D30S1, the N57S with 381 bhp, went into the M550d xDrive, the X5 and X6 M50d and the 750d xDrive. Sellers and even some dealers mix these up. It matters because the tri-turbo has a documented turbo-actuator failure pattern past 100,000 miles that the twin-turbo does not share to the same degree.
N57D30 problems: what actually fails?
Three things dominate. Swirl-flap bolts in the inlet manifold shear past 80,000 miles and the flap can enter a cylinder; the fix is preventative blanking at £250 to £450. The EGR cooler can crack internally and leak coolant into the intake past 70,000 miles (£600 to £1,100). The timing chain, at the gearbox end like the N47, stretches on neglected short-journey cars, though far less often than on the four-cylinder. On the tri-turbo N57S add the actuator conversation. See the full failure table below.
Which N57D30 is the best used buy?
The 258 bhp single-turbo N57D30O1 in a 2014-onwards 330d, 530d or X5 30d: Euro 6 so ULEZ-compliant, simplest turbo layout, 45 mpg on a run, 300,000 miles realistic. The twin-turbo 535d / 40d is a fine second choice if you test it hard on a full-throttle pull. The tri-turbo M550d / M50d is for enthusiasts with actuator paperwork and a specialist on speed-dial.
Which BMWs have the N57D30 engine?
The N57D30 went into the following cars, by output tier. N57D30U0 (204 bhp, single turbo): 325d (E90 / E91 / E92 2010-2013), 525d six-cylinder (F10 2010-2011); N57D30O0 (245 bhp, single turbo): 330d (E90 2008-2012), 530d (F10 2010-2011), 730d (F01 2008-2012), X5 xDrive30d (E70 2008-2010), X6 30d; N57D30O1 (258 bhp, single turbo (N57N)): 330d (F30 / F31 2012-2019), 430d, 530d (F10 / F11 2011-2017), 630d, 730d LCI, X3 xDrive30d (F25), X5 xDrive30d (F15 2013-2018), X6 30d; N57D30T0 (299 then 313 bhp, twin-turbo): 535d (F10 / F11 2010-2017), 640d, 740d (F01), X5 xDrive40d (E70 2010-2013, F15 2013-2018), X6 40d, X3 xDrive35d (F25, mostly US); N57D30T1 (313 bhp, twin-turbo (Euro 6)): 335d xDrive (F30 / F31 2013-2019), 435d xDrive (F32 / F33 / F36), X5 xDrive40d LCI (F15 2016-2018); N57D30S1 (381 bhp, tri-turbo (N57S)): M550d xDrive (F10 / F11 2012-2017), X5 M50d (E70 2012-2013, F15 2013-2018), X6 M50d (E71 / F16), 750d xDrive (F01 2012-2015). The two-letter family badge is N57; any listing that quotes the family code is talking about one of these.
Is the BMW N57D30 reliable?
Bimmer.AI scores the N57 family 7 out of 10, which makes the N57D30 a strong used buy with a short list of known preventatives. One of BMW's most capable diesel engines, the 530d's 3.0L straight-six is a long-distance tourer's dream: 500-mile tanks, 0-60 in under 6 seconds, real-world 45+ mpg on a run. Known for longevity (300,000+ miles with care) but the N57S tri-turbo (M550d, X5/X6 M50d and 750d only; the 535d is the twin-turbo unit) has chronic turbo actuator issues. Pre-2014 builds are Euro 5 and NOT ULEZ compliant, major issue for London buyers. With service history and known weak points addressed, one of the best all-round BMW powerplants ever made.
What does N57D30 mean?
N is the N-series engine generation (2001 to about 2015), 57 is the family number, D means diesel, longitudinal (rear-drive platform), 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.