[FD7683]

Hey guys, i'm just curious about how long these E9X N55's really last. If you own one, how many miles does it have? I don't see much high mileage N55's around (highest one i've seen had 130K Miles.

I'm in a debate between the N52, and the N55. I will probably get the N52 for cost purposes, but i'm just wondering the longevity of these N55 Engines from the E9X series since i don't see much high mileage examples.

[Smgs1992]

Take care of it and itll last. I have a friend with 140k on his with pure turbo. No major issues.
Drive them both and you’ll get your answer on which to get. Personally if its not your only car i see no reason to settle for a less powerful less fun car simply because some people on a forum scared you into thinking it’s gonna break every week.
My N54 (supposedly the least reliable bmw engine on the E9x chassis) has never left me stranded in almost 5yrs

[Tunafish]

The n55 is a good engine within context both the n55 and n52 have been in production for 11 years. This is a good run. The context is that n55 started production in 2009 which means to 335i that it was at the beginning of the production cycle, which also means they didn't work out all the bugs of a mass produced engine yet. This goes with any early production year engine.

In contrast the n52 started production in 2004 (ended 2015) which means to the 328i that it was more years to work out the bugs.. Just some food for thought.

I personally would expect to get 150k out of engine but would hope for 200k.

[Smgs1992]

Only 150k? If i find it i’ll post proof of a 360k mile 335i

[Smgs1992]

.

[Tunafish]

Yeah that is n54.. And i am stating that as personal expectations.

[Smgs1992]

Originally Posted by Tunafish

Yeah that is n54.. And i am stating that as personal expectations.

Which is supposedly less reliable.
Regardless though it applies directly to the statement you made above. Stating that since the N55 was a new engine at the time it would only get 150k miles out of it. That the N52 had been around awhile so it lasts longer.
Notice that N54 was a 2007 so it was brand new at the time yet got 2.5x more life than you suggested a new engine is capable of getting.

[Tunafish]

Yeah i am sure some n55 will get 300k+ miles.. I would not count on it or recommend someone counting on it.. If you want to thats on you.. Next

[hassmaschine]

300k+ mile N54 is an expensive unicorn. Also, 150k is not high miles.

[Tunafish]

Yep and as i started that i would expect to get 150k and hope for 200k..

I think that is a reasonable expectation for someone looking at a n55.. Thats what i did with mine. Got at 60k with 10k a year i expect engine to last for next eight years (already has been a year), i would be happy with that, anymore i figure will be a bonus. I also think my main concern is not the engine in this time frame but the top seals is going to be my next big ticket item..

[Veilside]

Currently have 118k miles on my n55 2011 e90. Maintenance that were done are common ones:

- PCV Valve
- Valve Cover Gasket
- OFHG
- Coolant Expansion tank
- Serpentine belt and tensioner
- Battery

Have yet to change waterpump, also have a few drips on the oil pan. Previous owner changed the waterpump at 71k miles.

N52 do have similar if not the same maintenance items to be changed. If that's the case, I'd take the n55 as it has more usable power for highway and city driving wise (overtake, merging, etc).

My car only had 1 previous owner before me, and had been maintained at the dealer its whole life. I'd suggest looking at the service records and find one that has been thoroughly maintained.

I believe there was a user here with 200k miles on his n55 e90. His username was cahme if I'm correct.

[Hoody007]

Originally Posted by hassmaschine

300k+ mile N54 is an expensive unicorn. Also, 150k is not high miles.

I thought so too, but looking at the service history of that 300K N54, it doesn't look too bad, honestly. Gives me hope for my N54 with 127K miles!

I've test driven a 250K N55 335i and the motor and gearbox seemed fine enough - it hadn't been maintained in other areas, however, which is why I passed on it.

[FD7683]

I have seen many cases of the Rod Bearings seizing after the OFHG, or maybe just by driving it.

Thats why i was wondering about how long they last.

[Gamb1t]

If I were to shop for a fun N55 bmw, I'd get the 135i. It's dct is so much more responsive than the e90's traditional automatic. The 1-er being more tossable and agile.
In terms of reliability and longevity with e90 engines:
N52 highest
N5x variants
N55
S65?
.
.
.
.
.
.
N54 lowest. The numerous 335i problem threads are proof.

[kart23]

I would go for a later model n55. I really do think that the early model n55 didn't have great software, there's lots of threads of the engine doing weird things for no apparent reason (stalling, surging, weird idles, etc.) The rod bearings I honestly don't know. I think there might be a problem, but I don't know if we'll ever get a definitive answer. If you're concerned, don't buy one, get an n52.

[fastboatster]

N54 is as reliable as any engine with iron cylinders can be. Most of the problems are auxiliaries such as turbos, gaskets, injectors and pumps. If those are replaced then the engine will happily go another 100kmiles. Rinse and repeat and you get to 300kmiles. I’d like to think of this as of buying the car for extra 5-10k of your original price. Say that 7k 335i is actually a 17 grand car, you just have an installment plan. Depending on your luck, it might be you or another person paying those installments. Imo, better to buy an n54 335i which needs turbos, has leaks and what not at a discount rather than buy a supposedly good one which can make you pay the installments any time.

[Welcome to NBA Jam]

Mine has 126k. No complaints. Everything on it that has gone wrong is shared across the platform.