technical f30 335i N55 bearings

[Liam H]

Hi there everyone! I'm new to this forum, and I have been wanting to ask a question regarding when to replace the rod bearing on my F30 335i PWG N55.

My car was owned from new and driven till about 127 000 kms by it's first owner, and then bought by a friend and was not driven too much. I am the third owner and the car is sitting on 138 000kms. The car is extremely well maintained with some tasteful mods such as MHD Stage 1, upgraded charge pipe and catless downpipe. The car has full BMW service history and is in super good condition, with lots of preventative maintenance . I am just curious for when I'll be doing rodbearings and what the whole job would cost me? I have been told that doing bearings around the 200 000km marking is a must. I just thought of getting some opinions on this.

Cheers!

2012 BMW F30 335i Luxury

 

[Holiman]

N55 pwg owner here... I'm on 220k km... Haven't been told otherwise wrt to bearing but that could be wrong.

Sent from my SM-S911B using Tapatalk

 

[Soprano890925]

Hey Liam
I'd suggest reaching out to @Clint@MMS AUTO, his very knowledgeable and reliable on BMW related maintenance and the like.
If anyone i going to guide on the right course of action it will be him.

 

[David Kunitz]

Bearings will only be an issue if you track or spin the car. Driving it hard is fine, my F30 335i has almost 400,000km now with original bearings.

Definitely no need to change them, only if the car has been abused

 

[Liam H]

Bearings will only be an issue if you track or spin the car. Driving it hard is fine, my F30 335i has almost 400,000km now with original bearings.

Definitely no need to change them, only if the car has been abused

That is absolutely amazing. I do not track the car at all, i like to floor it 2 or 3 times a week just to keep her awake haha, when she's up to temp. I always let her coldstart and idle for 5-10mins before driving too. The fact that your car has almost 400 000kms is absolutely astonishing!!! Just shows how great these motors are when well maintained. How has your experience been so far, any big repairs? I have a 2012 n55 pwg aswell. My car is sitting on 142 000kms and gets new oil and filters every 7000-9000kms.

 

[David Kunitz]

That is absolutely amazing. I do not track the car at all, i like to floor it 2 or 3 times a week just to keep her awake haha, when she's up to temp. I always let her coldstart and idle for 5-10mins before driving too. The fact that your car has almost 400 000kms is absolutely astonishing!!! Just shows how great these motors are when well maintained. How has your experience been so far, any big repairs? I have a 2012 n55 pwg aswell. My car is sitting on 142 000kms and gets new oil and filters every 7000-9000kms.

Thank you very much.

I have no doubt your car will last forever, letting it cold start before driving is important. I typically wait for the rpm to drop to 660rpm before setting off and keeping the engine below 2500rpm until it has reached 90°C.
And to let the engine idle for a minute or two before shutting off is also important.

I would like to make a YouTube video for you and others, of what I have replaced on my 335i and what to look out for in terms of maintenance on the N55. I'll post a link to it here if I get around to it

 

[Pisancho]

That is absolutely amazing. I do not track the car at all, i like to floor it 2 or 3 times a week just to keep her awake haha, when she's up to temp. I always let her coldstart and idle for 5-10mins before driving too. The fact that your car has almost 400 000kms is absolutely astonishing!!! Just shows how great these motors are when well maintained. How has your experience been so far, any big repairs? I have a 2012 n55 pwg aswell. My car is sitting on 142 000kms and gets new oil and filters every 7000-9000kms.

Because I did not buy my car new and I am the second owner I am doing mine. But only once the sump gasket starts leaking. I am also PWG with hybrid turbo etc. It will cost 27k to do. I do not know how the original owner drove it and his habits and that is why I will do mine. He was an older gentleman in his 50s, business owner etc. but the fact that the car is a 2013 and only had 83k on the clock (its on 113 now) and he did the 25k service intervals makes me not trust that the bearings are in the best state.

The car had a ton of sludge when the valve cover was done (short distance driving from the previous owner and hence the 83k in the 11 years he had it). It was sorted out by Xflow who used engine flush and did 3 oil changes to get it out and clean the engine. This is another reason i dont trust the bearings.

Since then, i service every 10k km. And do the usual warming up routine etc. Never floor it when cold and wait for my oil gauge to hit temp before I start playing. I do drag races for fun on the track and with friends every now and again and the car hasnt skipped a beat despite being a heavy girl (640i grand coupe). If it involves hard turns I baby it through and keep my speed low. It is a straight line queen lol.

The main suspect for the bearings though is the tracking as mentioned. The other is hard accelerations and braking when the oil level is low. The G forces move the oil around in the sump and all you need is a split second of there not being oil on the bearings for things to go sideways. I check my oil every week. And depending on how hard I drive the car I always top up every 3 months give or take or 2 to 3k km with half a litre to keep it full.

If you trust the first owner, then dont worry about it. I have major trust issues so I am doing mine. But I am pretty sure my bearings will get over 200k despite that. I will be adding a bigger turbo, fuelling etc so thats another reason for me doing my bearings. Preventive maintenance before modding is my motto.