[AWD Addict]

Originally Posted by AWD Addict

My '08 335xi has 135,000 miles on it. I've owned it since she was born (I ordered it custom) and drove it off the lot with 2 miles on it. Car has the sport package (so has the oil cooler). It's a daily driver with a mix of 50/50 highway and city driving. I'm a sporty driver, and apart from a couple autox runs since I bought it (which I don't plan any more of), the car has not and will not be raced.

Oil has been changed every 5,000 miles since inception. Plugs, coil packs, injectors etc are all regularly maintained, as is coolant and tranny fluid. Only wrinkle there is I'm now running Liquimoly instead of just the BMW spec'd castrol. I've done 3 oil analyses in the past 3 years, and they're all perfect. Car ran stock until end of warranty at 50,000 miles. I then added a VRSF 5.5" stepped intercooler, and a cobb stage 1+ tune. Turbos were replaced at ~85,000 due to a slight wastegate rattle (under warranty ) She's had a bunch of other typical stuff replaced over time (transfer case, clutch, water pump, hpfp, etc)

Car's been undergoing a broad refresh (new android screen for the i-drive, suspension/chassis upgrades, some exterior clean up) and is about to be 15 years old, which means no more emissions check. Car's going into the shop in a week for a new rustproofed subframe (the only thing on my undercarriage that's not immaculate), VRSF downpipes, new 02 sensors, an oil catch can, and intercooler flush (it's oily), and a couple other maintenance odds and ends. I'll probably do a wildly unnecessary compression/leak down test too. I also finally ditched the Cobb, and have been running the MHD tune for a month in preparation for the upcoming Stage 2+ setup.

I love this car. I'm pretty sure it loves me too. If my wife divorces me, I'm parking this thing on her side of the bed. My mechanic is suggesting I consider rod bearings given the whole story above. He's had a few 535xi's spin bearings, and did a motor swap on another 5 series where they checked the bearings, and at least one was cracked - rest were heavily scratched up. I've read this thread, and I'm generally on the "I take care of my car and don't track it, this is a waste of money" stance. I'm also a "if it ain't broke" type of guy. That said, I'll have the subframe off, and already be under there and spending money. Is this cheap insurance at this stage? Should I do this? I'm already dumping dough on the thing. I'm guessing all told this is another grand or so with labor.

Assuming this is a "yes, do it" the next question is:

1) Do I do the oil pump while I'm in there too? That probably makes the $1000 closer to $1800. I'm not pinching pennies here, but as noted previously, where does the preventative piece here stop?

2) Any strong feelings on which bearings? My mechanic likes BE, but theres Kolbenschmidt, OE, etc. I don't want to diminish this, but shit. They're strips of metal. Just pick a high quality group and go, right?

Thanks for the help! Flame suit on!!!

AA

Car went in today. Some updates:

1) I'm doing the oil pump while they're in there.
2) I'm doing the rod bearings. They're going to pull #1 first so we can take a peek, but I'm likely doing them either way.
3) New IC Hoses, clean IC oil out, add catch can.
4) New VRSF downpipes
5) New rustproofed front subframe to match my rustproofed rear one. Still can't get over how good the undercarriage on this car looks after 15 years in New England.

Plugs and coilpacks are less than a year old, but my injectors are 4 years old (~40k miles). I had a little rough idle a tank or two ago, but it's not too bad... Should I bite the bullet and do the injectors, or just wait and see if they're bitchy after the upgrades and new tune? Given the $3000 they're going to cost, I'm leaning on waiting....

[AWD Addict]

Got the car back on Friday. On this matter in particular (rod bearings), I'd say I'm happy I swapped them out just for peace of mind. I think the wear was generally mild but for cylinder 6, which was closer to moderate, but unlikely to become a problem in the near/medium term.

The photos I'm adding are the selected pics from over a dozen, as I tried to get the light to show these in the worst possible condition. Point being, you're looking at some carefully curated shots to highlight the wear. Personally I'd qualify these as smooth to the touch, with the lines really being on the surface only, and not materially penetrating into the bearing. Except for very few instances, there was no tangible scouring on these, just surficial linear markings.

Cylinder 6 showed the most wear, but not in scouring. It looks to me that the wear was even, but had started to push into the copper layer that I understand is below the outside coating. I'm not sure if that's a result from heat, contact or what.

I'd suggest if you bought this car used and don't know it's detailed history, this isn't a terrible preventative maintenance item to do, particularly if you're doing downpipes and already underneath the car with subframe off. If you know the cars been well maintained and properly treated for it's entire life, you could probably save a few bucks on this one.

In order from top to bottom

1) Cylinder 6 - you can see the discoloration on the left pretty well in this shot.
2) Cylinder 5 - I thought this one looked pretty good. Again, the lighting is making those lines look more like scours than they are.
3) Cyls 1-4 (from left to right). These all felt pretty smooth to the touch and showed what I think is mild wear, particularly for a car that's been Stage 1+ for the last 90,000 miles.

Thoughts?

[feuer]

AWD Addict Sorry. I have to tell you. Stage 1+ for 90k means nothing by itself. People should really stop using level of upgrades and especially mileage as reference points. What matters is how it was utilized and maintained. Could be stage 3 with 190k but driven gently. Or stock with 9k but tracked hard every weekend. Those bearings don’t look too good to me. Scoring, burn and dirt marks. I have seen plenty of n54/55 bearings (not on line) It’s difficult to predict but honestly my opinion is that they didn’t have much life left and good that you replaced them. Why you nigh ask? When bearings wear the wear is accelerating. Because debris go in oil and oil pressure drops. So gets worse fast.

[thormessiah]

So if an oil analysis can't be trusted to much, what's the next best way of knowing if they need to be changed out? Got 160K on mine, with bolt ons and upgraded turbos and will add port injection this spring.

[iqraceworks]

Originally Posted by thormessiah

So if an oil analysis can't be trusted to much, what's the next best way of knowing if they need to be changed out? Got 160K on mine, with bolt ons and upgraded turbos and will add port injection this spring.

Not sure I would say an oil analysis can't 100% be trusted. I would check your oil filter...if there are no shiny metal particles in it, an oil analysis says you are in good shape, and you know the car can been maintained properly....... I'd say there is a very good chance you are fine.

[feuer]

Originally Posted by iqraceworks

Not sure I would say an oil analysis can't 100% be trusted. I would check your oil filter...if there are no shiny metal particles in it, an oil analysis says you are in good shape, and you know the car can been maintained properly....... I'd say there is a very good chance you are fine.

A lot of moving parts in the engine that can wear and contaminate oil filter with shiny metal particles so shiny metal particles doesn’t automatically mean and points to rod bearings.

[iqraceworks]

Originally Posted by feuer

A lot of moving parts in the engine that can wear and contaminate oil filter with shiny metal particles so shiny metal particles doesn’t automatically mean and points to rod bearings.

Agreed.....but if you have metal shavings in the oil filter, you have problems......might as well pull the motor and go through it all at that point. But I would definitely check the rod bearings first.

[feuer]

Originally Posted by iqraceworks

Agreed.....but if you have metal shavings in the oil filter, you have problems......might as well pull the motor and go through it all at that point. But I would definitely check the rod bearings first.

3 years ago when I was building my single turbo n54 found metal pieces. Could not find where they come from. Found some more in the oil of the first two oil changes after the build. If you want miles, little short of 40k since. Hard driven miles. Many, many track days, many different people have driven it. It’s on the road almost every day. 30psi with PI. On -30c and +40c ambient. What I’m saying is not only that these engines are tough but that people should not go full blow panic if oil appears out of ordinary. It’s an engine and they do wear, all of them do. On n54 when people do oil pan gasket is good opportunity to replace the bearings too.

[AWD Addict]

Originally Posted by feuer

AWD Addict Sorry. I have to tell you. Stage 1+ for 90k means nothing by itself. People should really stop using level of upgrades and especially mileage as reference points. What matters is how it was utilized and maintained. Could be stage 3 with 190k but driven gently. Or stock with 9k but tracked hard every weekend. Those bearings don’t look too good to me. Scoring, burn and dirt marks. I have seen plenty of n54/55 bearings (not on line) It’s difficult to predict but honestly my opinion is that they didn’t have much life left and good that you replaced them. Why you nigh ask? When bearings wear the wear is accelerating. Because debris go in oil and oil pressure drops. So gets worse fast.

I was just providing context dude. Relax.

I think details like those provided are important context for the discussion.

On their condition, I'd generally agree. I don't think they show signs of imminent problems, but they're not immaculate by any means. Where I'm keeping the car for.the long haul, I'm pleased they were replaced.

Originally Posted by thormessiah

So if an oil analysis can't be trusted to much, what's the next best way of knowing if they need to be changed out? Got 160K on mine, with bolt ons and upgraded turbos and will add port injection this spring.

I'd be a bit tighter on my conclusion. I'd say that a black stone oil analysis isn't an exhaustive test to determine the condition of rod bearings in this car. I wouldn't cast out all oil analysis as completely useless based on just this discussion/result.

If those photos above are from a one owner car that's been meticulously maintained moderately tuned and driven, then a buyer of a pre-owned n54 with over 100,000 miles might be right to volunteer this work along with some other logical maintenance/upgrades. I'd consider a package in the area to include the the oil pan gasket and oil pump, My subframe needed to be replaced and I upgraded some exhaust so a lot of this work was happening anyways for long-term care.

The bearings are cheap if you're already in there. This thread was a huge help in making the decision (I wouldn't have done this otherwise), and I think my car is better off because of.it.

[iqraceworks]

Originally Posted by feuer

3 years ago when I was building my single turbo n54 found metal pieces. Could not find where they come from. Found some more in the oil of the first two oil changes after the build. If you want miles, little short of 40k since. Hard driven miles. Many, many track days, many different people have driven it. It’s on the road almost every day. 30psi with PI. On -30c and +40c ambient. What I’m saying is not only that these engines are tough but that people should not go full blow panic if oil appears out of ordinary. It’s an engine and they do wear, all of them do. On n54 when people do oil pan gasket is good opportunity to replace the bearings too.

I understand what you are saying....but unless you pull the motor apart and check the bearings, you are just guessing and hoping...

Anyone who finds a bunch of metal shavings in their oil filter.....and keeps running the motor without attempting to find the source is an idiot. I think everyone can agree on that. Sure, it may be nothing....but it may be something, and unless you attempt to find the source, you are just rolling the dice.

[Mustafa.e92]

My filter had some metal in it and oil analysis came back with a little silver in it. I ordered king std bearings and oem updated rod bolts. is this still the general consensus on what parts to use

[AWD Addict]

I used kolbenschmidt but king are very popular.

[TheMidnightNarwhal]

Originally Posted by iqraceworks

Agreed.....but if you have metal shavings in the oil filter, you have problems......might as well pull the motor and go through it all at that point. But I would definitely check the rod bearings first.

Idk, it seems some techs say a certain amount of metal is ok. I'm going through this myself so looked a lot online. Depends how much we are talking about here.

[iqraceworks]

Originally Posted by TheMidnightNarwhal

Idk, it seems some techs say a certain amount of metal is ok. I'm going through this myself so looked a lot online. Depends how much we are talking about here.

There is a huge different between metal "flakes"....and metal "particles".....and everything in between.

If I was changing my oil and I saw a few little shiny sparkles in the oil....something I couldn't really even feel with my fingers, I probably wouldn't worry too much. But, if I found some flakes big enough to pick up and look at, yeah...I would get a little worried. There are a lot of bearing and moving parts in an engine....lots of things could be generating metal debris. How much is OK is and will always be debatable.

In the end, the decision on what to do is left up to the person who owns the car.

[Mustafa.e92]

Originally Posted by iqraceworks

There is a huge different between metal "flakes"....and metal "particles".....and everything in between.

If I was changing my oil and I saw a few little shiny sparkles in the oil....something I couldn't really even feel with my fingers, I probably wouldn't worry too much. But, if I found some flakes big enough to pick up and look at, yeah...I would get a little worried. There are a lot of bearing and moving parts in an engine....lots of things could be generating metal debris. How much is OK is and will always be debatable.

In the end, the decision on what to do is left up to the person who owns the car.

My cars been pretty consistent with having some metal in the filter honestly it could be from anywhere but rod bearings are somewhat on my mind with the car having 180,000 kms single turbo and me beating the shit out of it constantly. I do my own work I don’t mind the labour for the peace of mind.

[feuer]

Originally Posted by AWD Addict

I used kolbenschmidt but king are very popular.

That’s what I have been using. They make the bearings for BMW.

[feuer]

Originally Posted by iqraceworks

I understand what you are saying....but unless you pull the motor apart and check the bearings, you are just guessing and hoping...

Anyone who finds a bunch of metal shavings in their oil filter.....and keeps running the motor without attempting to find the source is an idiot. I think everyone can agree on that. Sure, it may be nothing....but it may be something, and unless you attempt to find the source, you are just rolling the dice.

Yeah, I must be the biggest idiot, luckiest too

[iqraceworks]

Originally Posted by feuer

Yeah, I must be the biggest idiot, luckiest too

You said when you found metal in the oil filter that you went through everything and didn't find anything.......so you did exactly what I said, you investigated the problem. The right thing to do.

You go out of your way to start $hit with everyone don't you? Good lord....I bet you are lots of fun a parties aren't you

[AWD Addict]

Will you two just f*ck and get it over with? You're contaminating a decent discussion.

[TheMidnightNarwhal]

Originally Posted by iqraceworks

There is a huge different between metal "flakes"....and metal "particles".....and everything in between.

If I was changing my oil and I saw a few little shiny sparkles in the oil....something I couldn't really even feel with my fingers, I probably wouldn't worry too much. But, if I found some flakes big enough to pick up and look at, yeah...I would get a little worried. There are a lot of bearing and moving parts in an engine....lots of things could be generating metal debris. How much is OK is and will always be debatable.

In the end, the decision on what to do is left up to the person who owns the car.

For sure but I ask because I do need to make a decision myself.I agree big pieces like you describe a flake I can pick up with to fingers that would be cause to worry but I'm more on the topic of smaller pieces or shiny looking oil upon very close inspection. But yeah I like making decisions based on objective information rather than just subjective. Unforutnely this topic seems pretty subjective so in my case I will probably keep on as usual, time will tell. And try an oil analysis for the fun of it next oil change.

[feuer]

Originally Posted by iqraceworks

You said when you found metal in the oil filter that you went through everything and didn't find anything.......so you did exactly what I said, you investigated the problem. The right thing to do.

You go out of your way to start $hit with everyone don't you? Good lord....I bet you are lots of fun a parties aren't you

Oh, yeah, most definitely! I make all parties great.

[feuer]

Originally Posted by AWD Addict

Will you two just f*ck and get it over with? You're contaminating a decent discussion.

My sincere apologies for polluting your thread. I have tried. But it's very challenging for me not to engage with the forum expert.