The Lemon Index
BMW's 3.0 L single twin-scroll turbo inline-6 in the 2 Series, 3 Series, 4 Series, 5 Series, 7 Series, X1, X3, X4, X5, X6, model years 2010–2019. YouTube likes the 2017 best.
Middle of the pack: YouTube owner tone 50/100, #80 of 165 engines with a YouTube study (in the middle third); no engine-related recall on record.
Reliability by year
YouTube videos are most positive about the 2017 (54) and least about the 2011 (43); neighboring years share many of the same videos, so small gaps mean little.
Owner score = the whole car's Lemon Index where this was its only engine that year; a gray dot means the model shared engines, so the number isn't this engine's alone. How we count
How each number is matched to the engine: (a) complaints filed under a version name that used only this engine that year (e.g. "335I"); (b) the model had only this engine that year, so its Lemon Index (complaints per car sold vs the average car) applies to every car with this engine; "all engines combined" = the model had several engines under one name, so its number is not this engine's alone. Owner complaints cover the whole car (brakes, air bags, electrics ...), not only the engine. None of these is a failure rate. YouTube tone = how positive the videos are, 0–100, from titles and transcripts that name the engine or a version that used it. A video whose title names no model year counts toward every year of its generation, so neighboring years share most of their videos.
All the numbers, year by year
| Year | Cars with it | Owner complaints | Complaints naming "N55" | YouTube says | Top complaint areas |
|---|---|---|---|---|---|
| 2010 | BMW 5 Series 535i GT | all engines combined: BMW 5 Series Index 75 | 0 | not enough videos | — |
| 2011 | BMW 3 Series 335ci, 335ci xDrive, 335i, 335i xDrive BMW 5 Series 535i, 535i xDrive BMW X5 X5 xDrive35i BMW X3 X3 xDrive35i BMW X6 X6 xDrive35i | 298 complaints (a: filed as 335i, 535i) | 12 | 43 (68 videos, 28 naming 2011) | engine, fuel system, air bags |
| 2012 | BMW 3 Series 335ci, 335i, 335i xDrive BMW 5 Series 535i, 535i xDrive, ActiveHybrid 5 BMW X5 X5 xDrive35i BMW X3 X3 xDrive35i BMW X6 X6 xDrive35i | 102 complaints (a: filed as 335i, 535i) | 2 | 48 (53 videos, 18 naming 2012) | air bags, engine, tires |
| 2013 | BMW 3 Series 335i, 335i xDrive, ActiveHybrid 3 BMW 5 Series 535i, 535i xDrive, ActiveHybrid 5 BMW 7 Series 740Li, 740Li xDrive, 740i, ActiveHybrid 7L BMW X5 X5 xDrive35i BMW X3 X3 xDrive35i BMW X6 X6 xDrive35i BMW X1 X1 xDrive35i | 104 complaints (a: filed as 335i, 535i, 740i) | 5 | 51 (68 videos, 31 naming 2013) | engine, electrical, air bags |
| 2014 | BMW 3 Series 335i, 335i xDrive, ActiveHybrid 3 BMW 5 Series 535i, 535i xDrive, ActiveHybrid 5 BMW 7 Series 740Li, 740Li xDrive, 740i, ActiveHybrid 7L BMW X5 X5 sDrive35i, X5 xDrive35i BMW X3 X3 xDrive35i BMW X6 X6 xDrive35i BMW X1 X1 xDrive35i BMW 4 Series 435i, 435i xDrive BMW 2 Series M235i | 94 complaints (a: filed as 335i, 535i, 740i, 435i, M235i) | 2 | 52 (87 videos, 36 naming 2014) | engine, fuel system, electrical |
| 2015 | BMW 3 Series 335i, 335i xDrive, ActiveHybrid 3 BMW 5 Series 535i, 535i xDrive, ActiveHybrid 5 BMW 7 Series 740Li, 740Li xDrive, 740i, ActiveHybrid 7L BMW X5 X5 sDrive35i, X5 xDrive35i BMW X3 X3 xDrive35i BMW X6 X6 sDrive35i, X6 xDrive35i BMW X1 X1 xDrive35i BMW 4 Series 435i, 435i xDrive BMW 2 Series M235i, M235i xDrive BMW X4 X4 xDrive35i | 59 complaints (a: filed as 335i, 535i, 740i, 435i, M235i) | 2 | 51 (103 videos, 51 naming 2015) | electrical, engine, body & structure |
| 2016 | BMW 3 Series 335i xDrive BMW 5 Series 535i, 535i xDrive, ActiveHybrid 5 BMW X5 X5 sDrive35i, X5 xDrive35i BMW X3 X3 xDrive35i BMW X6 X6 sDrive35i, X6 xDrive35i BMW 4 Series 435i, 435i xDrive BMW 2 Series M2, M235i, M235i xDrive BMW X4 X4 M40i, X4 xDrive35i | 34 complaints (a: filed as 335i, 535i, 435i, M235i) | 1 | 52 (89 videos, 38 naming 2016) | air bags, other, engine |
| 2017 | BMW 5 Series 535i, 535i xDrive BMW X5 X5 sDrive35i, X5 xDrive35i BMW X3 X3 xDrive35i BMW X6 X6 sDrive35i, X6 xDrive35i BMW 2 Series M2 BMW X4 X4 M40i | all engines combined: BMW 5 Series Index 21; BMW X5 Index 50; BMW X3 Index 66; BMW X6 3 complaints; BMW 2 Series 31 complaints; BMW X4 3 complaints | 0 | 54 (39 videos, 33 naming 2017) | — |
| 2018 | BMW X5 X5 sDrive35i, X5 xDrive35i BMW X6 X6 sDrive35i, X6 xDrive35i BMW 2 Series M2 BMW X4 X4 M40i | all engines combined: BMW X5 Index 40; BMW X6 4 complaints; BMW 2 Series 10 complaints; BMW X4 11 complaints | 0 | 46 (10 videos, 5 naming 2018) | — |
| 2019 | BMW X6 X6 sDrive35i, X6 xDrive35i | all engines combined: BMW X6 5 complaints | 0 | not enough videos | — |
Every US version with this engine
| Model and version | Years | Power |
|---|---|---|
| BMW 3 Series 335ci | 2011–12 | 302 hp · 295 lb-ft |
| BMW 3 Series 335ci xDrive | 2011 | 302 hp · 295 lb-ft |
| BMW 3 Series 335i | 2011–15 | 302 hp · 295 lb-ft |
| BMW 3 Series 335i xDrive | 2011–16 | 302 hp · 295 lb-ft |
| BMW 3 Series ActiveHybrid 3 | 2013–15 | 335 hp |
| BMW 5 Series 535i GT | 2010 | 302 hp · 295 lb-ft |
| BMW 5 Series 535i | 2011–17 | 302 hp · 295 lb-ft |
| BMW 5 Series 535i xDrive | 2011–17 | 302 hp · 295 lb-ft |
| BMW 5 Series ActiveHybrid 5 | 2012–16 | 335 hp |
| BMW 7 Series 740Li | 2013–15 | 315 hp · 332 lb-ft |
| BMW 7 Series 740Li xDrive | 2013–15 | 315 hp · 332 lb-ft |
| BMW 7 Series 740i | 2013–15 | 315 hp · 332 lb-ft |
| BMW 7 Series ActiveHybrid 7L | 2013–15 | — |
| BMW X5 X5 xDrive35i | 2011–18 | 302 hp · 295 lb-ft |
| BMW X5 X5 sDrive35i | 2014–18 | 302 hp · 295 lb-ft |
| BMW X3 X3 xDrive35i | 2011–17 | 302 hp · 295 lb-ft |
| BMW X6 X6 xDrive35i | 2011–19 | 302 hp · 295 lb-ft |
| BMW X6 X6 sDrive35i | 2015–19 | 302 hp · 295 lb-ft |
| BMW X1 X1 xDrive35i | 2013–15 | 302 hp · 295 lb-ft |
| BMW 4 Series 435i | 2014–16 | 302 hp · 295 lb-ft |
| BMW 4 Series 435i xDrive | 2014–16 | 302 hp · 295 lb-ft |
| BMW 2 Series M235i | 2014–16 | 322 hp |
| BMW 2 Series M235i xDrive | 2015–16 | 322 hp |
| BMW 2 Series M2 | 2016–18 | 365 hp · 343 lb-ft |
| BMW X4 X4 xDrive35i | 2015–16 | 302 hp · 295 lb-ft |
| BMW X4 X4 M40i | 2016–18 | 355 hp · 343 lb-ft |
Versions and years: EPA (fueleconomy.gov). Engine and power: Wikipedia, BMW N55 (BMW ratings; US figures can differ by a few hp).
Quick answers
What cars have the BMW N55 engine?
In the US: the 2 Series, 3 Series, 4 Series, 5 Series, 7 Series, X1, X3, X4, X5, X6, model years 2010–2019. See the version table for each one.
Is the N55 reliable?
Mostly. YouTube owner tone 50/100, #80 of 165 engines with a YouTube study (in the middle third); no engine-related recall on record. The most owner complaints (about any part of the car) filed under version names that used this engine were for the 2011 (298). Counts follow sales, so this is not a failure rate. Government complaints are filed by model and year, not engine, and they cover the whole car, so none of these numbers is an engine failure rate. We only credit a number to this engine where the version name or the model year leaves no doubt. Have any used car inspected.
How much horsepower does the N55 make?
BMW rated it at 302 to 365 hp in US versions, depending on the car and year.