3 ms·

BMW got much better since the switch to B series engines, N series era was horrible. Timing chains between the engine and gearbox are a pain point though, they

BMW got much better since the switch to B series engines, N series era was horrible. Timing chains between the engine and gearbox are a pain point though, they need to be replaced with mileage.

tricky 3y ago
Not all N series engines are awful. The N52, while not as amazing as the previous M52/M54 engines, is a fantastic, reliable engine. However, the 4 cylinder N20 used between 2011-2017 is the worst. Faulty timing chain guides often fail and immediately grenade the engine. They were so bad there was even a class action lawsuit
- avar 3y ago
  The N53 is even better, BMW phased out the N52 in favor of it, except in developing economies with subpar fuel standards.
  - tom_ 3y ago
    The N53 is notably one of bmw's less reliable engines. Everything that goes wrong with it is tedious to debug and ends up hugely expensive to fix because you always end up needing to replace several pricey injectors. Then it breaks again later. The N52 seems rather better, as all its common faults are relatively cheap to fix.
    - michalf6 3y ago
      Yup, they switched to piezoelectric injectors in N53 which are crazy expensive and regularly fail.
jankyxenon 3y ago
The B58 is such a great all around engine. Performance, reliability, efficiency, upgradeability. Heck, even Toyota used it in their sports car (Supra)
wizee 3y ago
The B58 and B48 are quite impeccably good engines, both in terms of reliability and also performance/response. I had an excellent experience with my B58-powered M240i. I've also never heard anyone needing to do anything in practice with timing chains on these engines, even at high mileage. It seems the whole car would be worn out before the timing chain wears out, provided you use decent quality oil and don't neglect oil changes. The older N52 engine is also very solid and reliable, my high mileage 2006 330i (E90) has been rock solid reliable in its powertrain. My mechanic told me the N20 engine is terrible though, he has encountered an absurd number of them failing. The N54 is solid enough mechanically, though they get HPFP issues and need occasional cleaning of soot/gunk from valves.
- michalf6 3y ago
  I'm shopping around for a B48 powered car, and there have been instances of stretched chains at like 180000km. It's worse in B47, which carries over the same timing parts as N47 and it's generally acknowledged it's best to replace the chain at 120000km there. 6cyls seem to fare better, my guess is the pulling forces on the chain are spaced more evenly.

BMW got much better since the switch to B series engines, N series era was horrible. Timing chains between the engine and gearbox are a pain point though, they need to be replaced with mileage.

tricky 3y ago

Not all N series engines are awful. The N52, while not as amazing as the previous M52/M54 engines, is a fantastic, reliable engine. However, the 4 cylinder N20 used between 2011-2017 is the worst. Faulty timing chain guides often fail and immediately grenade the engine. They were so bad there was even a class action lawsuit

avar 3y ago
The N53 is even better, BMW phased out the N52 in favor of it, except in developing economies with subpar fuel standards.
- tom_ 3y ago
  The N53 is notably one of bmw's less reliable engines. Everything that goes wrong with it is tedious to debug and ends up hugely expensive to fix because you always end up needing to replace several pricey injectors. Then it breaks again later. The N52 seems rather better, as all its common faults are relatively cheap to fix.
  - michalf6 3y ago
    Yup, they switched to piezoelectric injectors in N53 which are crazy expensive and regularly fail.

jankyxenon 3y ago

The B58 is such a great all around engine. Performance, reliability, efficiency, upgradeability. Heck, even Toyota used it in their sports car (Supra)

wizee 3y ago

The B58 and B48 are quite impeccably good engines, both in terms of reliability and also performance/response. I had an excellent experience with my B58-powered M240i. I've also never heard anyone needing to do anything in practice with timing chains on these engines, even at high mileage. It seems the whole car would be worn out before the timing chain wears out, provided you use decent quality oil and don't neglect oil changes. The older N52 engine is also very solid and reliable, my high mileage 2006 330i (E90) has been rock solid reliable in its powertrain. My mechanic told me the N20 engine is terrible though, he has encountered an absurd number of them failing. The N54 is solid enough mechanically, though they get HPFP issues and need occasional cleaning of soot/gunk from valves.

michalf6 3y ago
I'm shopping around for a B48 powered car, and there have been instances of stretched chains at like 180000km. It's worse in B47, which carries over the same timing parts as N47 and it's generally acknowledged it's best to replace the chain at 120000km there. 6cyls seem to fare better, my guess is the pulling forces on the chain are spaced more evenly.