F30 N20 vs N55 Common Problems & Reliability Issues

sadjoe · 06-13-2021, 12:00 PM

Hello everyone,

Could you share your thoughts regarding "F30 N20 vs N55 Common Problems & Reliability Issues"
I was read a lot about these engines but nothing compare to the real deal owner answers.

- Which year is preferable? Like At least 2014
- What are the most common problems. After buying the car it's must to look into these problems afterwards consider changing/fixing

Example (most common problems):
- Timing Chain
- Valve Cover and Valve Cover Gasket
- Water Pump Failure
- Leaking Oil Filter Housing Gasket
- VANOS Solenoid Failure
- High Pressure Fuel Pump Failure (HPFP) – Mostly older models

- Real consumption (stock car)
- City (with 50-60 km/h)
- Highway (100-140km/h)
Second thoughts should i think about B48 and B58 instead of N20 and N55

More words about the xDrive system and what to expect there as weak spots and repairs.

In the end I am looking mostly for reliability. Less problems and less expensive repairs.

Thank you in advance.

Boostedphil698 · 06-13-2021, 08:33 PM

Quote:

Originally Posted by sadjoe

Hello everyone,

Could you share your thoughts regarding "F30 N20 vs N55 Common Problems & Reliability Issues"
I was read a lot about these engines but nothing compare to the real deal owner answers.

- Which year is preferable? Like At least 2014
- What are the most common problems. After buying the car it's must to look into these problems afterwards consider changing/fixing

Example (most common problems):
- Timing Chain
- Valve Cover and Valve Cover Gasket
- Water Pump Failure
- Leaking Oil Filter Housing Gasket
- VANOS Solenoid Failure
- High Pressure Fuel Pump Failure (HPFP) – Mostly older models

- Real consumption (stock car)
- City (with 50-60 km/h)
- Highway (100-140km/h)
Second thoughts should i think about B48 and B58 instead of N20 and N55

More words about the xDrive system and what to expect there as weak spots and repairs.

In the end I am looking mostly for reliability. Less problems and less expensive repairs.

Thank you in advance.

You're buying a BMW, it will never not have at least few expensive repairs. valve cover, and oil filter housing gasket are the both you'll never escape. The N20 timing chain fix is an expensive endeavor. If you are looking for the most reliability I'd go buy a Toyota.....they never break. Now, the more reliable motor is the N55 or B58. 6 cylinders are just what BMW does best.

sadjoe · 06-14-2021, 06:45 AM

Quote:

Originally Posted by Boostedphil698

You're buying a BMW, it will never not have at least few expensive repairs. valve cover, and oil filter housing gasket are the both you'll never escape. The N20 timing chain fix is an expensive endeavor. If you are looking for the most reliability I'd go buy a Toyota.....they never break. Now, the more reliable motor is the N55 or B58. 6 cylinders are just what BMW does best.

Well,
I don't like Toyota. If we talk about the total reliability than we go with Mazda.
I am not saying having a BMW you don't have any problems.
The point is to having less problem like "timing chain" causing by BMW by default.
About fixing the time chain what do you mind? If this is changing the time chain kit this is not an issue.

Rockinryan2424 · 06-14-2021, 08:34 AM

Quote:

Originally Posted by sadjoe

Quote:

Originally Posted by Boostedphil698

You're buying a BMW, it will never not have at least few expensive repairs. valve cover, and oil filter housing gasket are the both you'll never escape. The N20 timing chain fix is an expensive endeavor. If you are looking for the most reliability I'd go buy a Toyota.....they never break. Now, the more reliable motor is the N55 or B58. 6 cylinders are just what BMW does best.

Well,
I don't like Toyota. If we talk about the total reliability than we go with Mazda.
I am not saying having a BMW you don't have any problems.
The point is to having less problem like "timing chain" causing by BMW by default.
About fixing the time chain what do you mind? If this is changing the time chain kit this is not an issue.

Honestly I thought I had a stroke trying to read this.

auburnf30x · 06-14-2021, 08:43 AM

Factory N20 issues include the timing chain and transfer case. Both have available parts to permanently fix the issue.

N55 does not suffer from timing chain issues, however the transfer case has the same weak point. That being said, since the failure is accelerated by prominent engine vibration and the N55 produces very little, transfer case failures with the N55 are very rare.

Stock for stock, the N55 is likely to be more reliable. You mentioned that you were also considering the B48, if you want to go the four cylinder route, that would also serve you well. Both the timing chain and transfer case issues were fixed by the time the B48 came around.

sspade · 06-14-2021, 09:25 AM

Have approximately ~90k driven over two vehicles with the N20 motor (both RWD) and have literally only had one issue... the coolant thermostat replaced on my 2014, covered under extended factory warranty (free of charge).

In my experience this motor has been extremely reliable although not known for being as smooth or quiet running as inline six brethren.

Run quality fuel and change oil often. Don't abuse when cold.

35mpg highway cruising at 80mph.

Preferable to purchase an N20 with a mid to late 2015 build date.

hooligan_G01 · 06-14-2021, 09:41 AM

Quote:

Originally Posted by Rockinryan2424

Honestly I thought I had a stroke trying to read this.

And how is your written Bulgarian?

This is an international forum, you know.

Rockinryan2424 · 06-14-2021, 03:24 PM

Quote:

Originally Posted by hooligan_F36

Quote:

Originally Posted by Rockinryan2424

Honestly I thought I had a stroke trying to read this.

And how is your written Bulgarian?

This is an international forum, you know.

Google translate is a hell of a thing or don't you have that in Bulgaria

Gen13 F36 · 06-14-2021, 08:34 PM

Go either motor, like everyone said it's an expensive car to repair but I see 80s, 90, 2000s and 2010s running around....maybe those are properly maintain BMW, who knows

Good luck

eluded · 06-15-2021, 03:03 AM

The0pportunist · 06-15-2021, 04:40 AM

I've had my F30 335i (N55) for a couple years now. It was until last month the most reliable car i've ever had. Noticed smoke creeping up from under the hood at standstill traffic. Ended up having the valve cover gasket & oil filter gasket changed under warranty.

If you can, get an extended warranty for absolute peace of mind.

hooligan_G01 · 06-15-2021, 09:55 AM

Quote:

Originally Posted by Rockinryan2424

Google translate is a hell of a thing or don't you have that in Bulgaria

I'm not in Bulgaria.

mousefarmer · 06-15-2021, 11:23 AM

2012 335i F30

I've noticed leaky window seals on front two windows that makes car sound like an economy car at highway speeds. The car uses about 1/2 a quart oil every 5000 miles.

The harmonic balancer appears to have a slight wobble too that is noticeable when idling that makes it sound less than perfect as it causes the tensioner to spring back and forth.

Sometimes there have been mystery noises when gassing hard from turbo that have appeared and vanished.

Other times when pulling into garage before shutting off engine there is screech noise which is probably pcv or vent hose diaphragm failing which eventually requires new valve cover

M Smurf · 06-15-2021, 11:36 AM

Quote:

Originally Posted by mousefarmer

Other times when pulling into garage before shutting off engine there is screech noise which is probably pcv or vent hose diaphragm failing which eventually requires new valve cover

I've noticed what I think you're describing here. You think it's the Valve Cover gasket that needs replacing? Would there not be evidence of an oil leak?

culpability · 06-16-2021, 02:05 PM

BMW fixed the N20 timing chain issue with their 2016 and up N20s, although I believe the B48 became available around that same time, personally I'd go for the B48 over the N20, should be priced almost identically but the B48 seems to have a bit higher of a tuning ceiling with less of the N20's problems.

06-13-2021, 12:00 PM	#1
sadjoe Registered 1 Rep 4 Posts Drives: F30 Join Date: Jun 2021 Location: Bulgaria iTrader: (0)	F30 N20 vs N55 Common Problems & Reliability Issues Hello everyone, Could you share your thoughts regarding "F30 N20 vs N55 Common Problems & Reliability Issues" I was read a lot about these engines but nothing compare to the real deal owner answers. - Which year is preferable? Like At least 2014 - What are the most common problems. After buying the car it's must to look into these problems afterwards consider changing/fixing Example (most common problems): - Timing Chain - Valve Cover and Valve Cover Gasket - Water Pump Failure - Leaking Oil Filter Housing Gasket - VANOS Solenoid Failure - High Pressure Fuel Pump Failure (HPFP) – Mostly older models - Real consumption (stock car) - City (with 50-60 km/h) - Highway (100-140km/h) Second thoughts should i think about B48 and B58 instead of N20 and N55 More words about the xDrive system and what to expect there as weak spots and repairs. In the end I am looking mostly for reliability. Less problems and less expensive repairs. Thank you in advance.
	Appreciate 0 Tweet Quote

06-14-2021, 08:43 AM	#5
auburnf30x Lieutenant 435 Rep 562 Posts Drives: 2017 BMW 330i xDrive Join Date: Jan 2021 Location: Auburn, AL iTrader: (0) Garage List 2017 BMW 330i xDrive [8.50]	Factory N20 issues include the timing chain and transfer case. Both have available parts to permanently fix the issue. N55 does not suffer from timing chain issues, however the transfer case has the same weak point. That being said, since the failure is accelerated by prominent engine vibration and the N55 produces very little, transfer case failures with the N55 are very rare. Stock for stock, the N55 is likely to be more reliable. You mentioned that you were also considering the B48, if you want to go the four cylinder route, that would also serve you well. Both the timing chain and transfer case issues were fixed by the time the B48 came around. __________________ 2017 330i xDrive Imperial Blue Exterior / Venetian Beige Leather with Oyster Accent Interior / Anthracite Wood Trim
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06-14-2021, 09:25 AM	#6
sspade Major General 2465 Rep 5,457 Posts Drives: F30 Join Date: Oct 2017 Location: Stevenson, WA iTrader: (3) Garage List 2016 BMW 320i [7.87] 2014 BMW 328i [6.83]	Have approximately ~90k driven over two vehicles with the N20 motor (both RWD) and have literally only had one issue... the coolant thermostat replaced on my 2014, covered under extended factory warranty (free of charge). In my experience this motor has been extremely reliable although not known for being as smooth or quiet running as inline six brethren. Run quality fuel and change oil often. Don't abuse when cold. 35mpg highway cruising at 80mph. Preferable to purchase an N20 with a mid to late 2015 build date. Last edited by sspade; 06-14-2021 at 09:35 AM..
	Appreciate 2 RMachuca3d723.50 razzy53082.00 Quote

06-14-2021, 08:34 PM	#9
Gen13 F36 Brigadier General 1599 Rep 3,752 Posts Drives: 428i Gran Coupe Join Date: Nov 2017 Location: Los Angeles, CA iTrader: (1)	Go either motor, like everyone said it's an expensive car to repair but I see 80s, 90, 2000s and 2010s running around....maybe those are properly maintain BMW, who knows Good luck
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06-15-2021, 03:03 AM	#10
eluded 2JZ-GTE 3032 Rep 3,992 Posts Drives: 340 6MT, 50e, others Join Date: Nov 2015 Location: Sofia iTrader: (0)	__________________ A man who views the world the same at 50 as he did at 20 has wasted 30 years of his life.
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06-15-2021, 04:40 AM	#11
The0pportunist Major 471 Rep 1,268 Posts Drives: F30 335i Join Date: Sep 2012 Location: London iTrader: (0)	I've had my F30 335i (N55) for a couple years now. It was until last month the most reliable car i've ever had. Noticed smoke creeping up from under the hood at standstill traffic. Ended up having the valve cover gasket & oil filter gasket changed under warranty. If you can, get an extended warranty for absolute peace of mind.
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06-15-2021, 11:23 AM	#13
mousefarmer First Lieutenant 133 Rep 323 Posts Drives: 2007 328i, 2006 330i Join Date: Apr 2019 Location: N/A iTrader: (0)	2012 335i F30 I've noticed leaky window seals on front two windows that makes car sound like an economy car at highway speeds. The car uses about 1/2 a quart oil every 5000 miles. The harmonic balancer appears to have a slight wobble too that is noticeable when idling that makes it sound less than perfect as it causes the tensioner to spring back and forth. Sometimes there have been mystery noises when gassing hard from turbo that have appeared and vanished. Other times when pulling into garage before shutting off engine there is screech noise which is probably pcv or vent hose diaphragm failing which eventually requires new valve cover
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06-16-2021, 02:05 PM	#15
culpability Private First Class 82 Rep 133 Posts Drives: 2018 440i Gran Coupe Join Date: Jun 2020 Location: North Carolina iTrader: (0)	BMW fixed the N20 timing chain issue with their 2016 and up N20s, although I believe the B48 became available around that same time, personally I'd go for the B48 over the N20, should be priced almost identically but the B48 seems to have a bit higher of a tuning ceiling with less of the N20's problems.
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