Rod bearings

[XMetal]

If you haven't done an oil analysis up to this point, I wouldn't bother until after you had your rod bearings changed. Then start doing oil analysis on every oil change after that. The thing with running oil analysis is that you'll have to monitor trends, not just a single analysis. A single snapshot won't yield much useful information. Take a look at my thread over on Zpost and you'll see why a single snapshot may even give you a false sense of security => https://www.zpost.com/forums/showthread.php?t=1461006&highlight=oil+analysis

Let's say, you've only done one oil analysis and the result that you got lined up with mine on that 54.8k mile analysis. All the wear metals looked fine, but look at my bearings when they were taken apart after that analysis!

There's always some inherent risks opening up the engine, but you have to ask yourself what's the risk if you don't replace those bearings? Only you can weigh in whether the risks are worth that peace of mind...whatever let you sleep at night.

 

[abar121]

Thanks for posting, a great read on that thread.

I see what you mean about the single reading at 54.8k, but that you got extremely high lead content and possible bearing wear from your first two samples, before trying non-OE recommended oil / additives, which clearly impact the later analysis.

So that's also great information to have and possibly act earlier on.

 

[Skye 1872]

If you haven't done an oil analysis up to this point, I wouldn't bother until after you had your rod bearings changed. Then start doing oil analysis on every oil change after that. The thing with running oil analysis is that you'll have to monitor trends, not just a single analysis. A single snapshot won't yield much useful information. Take a look at my thread over on Zpost and you'll see why a single snapshot may even give you a false sense of security => https://www.zpost.com/forums/showthread.php?t=1461006&highlight=oil+analysis

Let's say, you've only done one oil analysis and the result that you got lined up with mine on that 54.8k mile analysis. All the wear metals looked fine, but look at my bearings when they were taken apart after that analysis!

There's always some inherent risks opening up the engine, but you have to ask yourself what's the risk if you don't replace those bearings? Only you can weigh in whether the risks are worth that peace of mind...whatever let you sleep at night.

Thanks very much for that very interesting read

 

[R60BBA]

Darren Wood.

http://www.darren-wood.com/

Ensure you go for Genuine BMW bearings and bolts. As yours has M10 bolts - avoid ARP at all costs.

 

[PDJ]

Ensure you go for Genuine BMW bearings and bolts. As yours has M10 bolts - avoid ARP at all costs.

And the reason being?

 

[R60BBA]

ARP M10 bolts were originally designed for the S50 engine (E36 M3). They suffer from a torque issue which can push the rod bore out of round.

Would only recommend ARP M11 bolts for rod bearings services, but these cannot be used for the S54 in the Z4M (as they are designed for the S54 in pre-facelift E46 M3s).

 

[aymamibrockway]

I bought mine at 116,000 miles and had spotty records, no indication of bearing work. I got it done and the mechanic said from the looks of them they had never been changed (and were way past due). Scary!

 

[tomscott]

I bought mine at 116,000 miles and had spotty records, no indication of bearing work. I got it done and the mechanic said from the looks of them they had never been changed (and were way past due). Scary!

Point proven in terms of cars with all milages can be anywhere on the spectrum. They are worn but ive seen far worse than this at 116k they've done pretty well. No question they needed doing tho.

For example these were 107k on an E46 M3.. these are worse but these were earlier bearings than in the Z4M

 

[Mikey_Boy]

For peace of mind get them changed out. Bottom line is that S54 rod bearings are too narrow so they will wear out - as a precaution, a few folks recommend changing every 50k miles.

I had mine done at 69k and they were cabbaged - I used SJR in Chester. M trained technician who takes his time to get the job done right. All OEM hardware.

 

[Skye 1872]

Now have all parts needed so the rod bearings will be getting changed in the next couple of weeks, i will post some images of the old rod bearings for anyone interested

 

[S54 PILOT]

14 years old with 128k us miles, don't see any reason of changing them at 40k

 

[rdm05z4]

Oh @$@$!! Reading this post now I know what am scheduling to get done this winter. Just went over 200k in my 05 and per Maintenance history Rod Bearings never done. The car does have a great maintenance history. oil changes every 3-5k etc. All work done by BMW dealer or Indy but looks like way overdue for Rod Bearings. While they are in there any other items should have inspected / replaced? This is just another reason why this forum is important providing critical information about our beloved cars. Car does have original Vanos and clutch. Showing no issues and for peace of mind just had BMW dealer go over the whole car for issues recommendations given mileage etc. Clean bill of health came back. And yes some shops are more reputable then others. But am sure if the stealer Dealer even thought they could make some $$$ they would have recommended work. Not that would get work done at dealer but at Indy but dealer gives possible issues list to go from.

 

[S54 PILOT]

There is no S54 engine on the z4 back in 2005, this bearing Issue is specific to 2006-2008 Z4m with s54 engine only
So relax your bearings never have to be done

Oh @$@$!! Reading this post now I know what am scheduling to get done this winter. Just went over 200k in my 05 and per Maintenance history Rod Bearings never done. The car does have a great maintenance history. oil changes every 3-5k etc. All work done by BMW dealer or Indy but looks like way overdue for Rod Bearings. While they are in there any other items should have inspected / replaced? This is just another reason why this forum is important providing critical information about our beloved cars. Car does have original Vanos and clutch. Showing no issues and for peace of mind just had BMW dealer go over the whole car for issues recommendations given mileage etc. Clean bill of health came back. And yes some shops are more reputable then others. But am sure if the stealer Dealer even thought they could make some $$$ they would have recommended work. Not that would get work done at dealer but at Indy but dealer gives possible issues list to go from.

 

[rdm05z4]

There is no S54 engine on the z4 back in 2005, this bearing Issue is specific to 2006-2008 Z4m with s54 engine only
So relax your bearings never have to be done

S54Pilot Thanks for the quick reply information and peace of mind. Again thanks to all who post on this forum everyday I learn more and more.

Oh @$@$!! Reading this post now I know what am scheduling to get done this winter. Just went over 200k in my 05 and per Maintenance history Rod Bearings never done. The car does have a great maintenance history. oil changes every 3-5k etc. All work done by BMW dealer or Indy but looks like way overdue for Rod Bearings. While they are in there any other items should have inspected / replaced? This is just another reason why this forum is important providing critical information about our beloved cars. Car does have original Vanos and clutch. Showing no issues and for peace of mind just had BMW dealer go over the whole car for issues recommendations given mileage etc. Clean bill of health came back. And yes some shops are more reputable then others. But am sure if the stealer Dealer even thought they could make some $$$ they would have recommended work. Not that would get work done at dealer but at Indy but dealer gives possible issues list to go from.

 

[Skye 1872]

Images of my rod bearings removed today at 40,000 miles

 

[Smartbear]

Images of my rod bearings removed today at 40,000 miles 12973707-C4DC-40B8-A50C-0A54D9B73AB0.jpeg

Some of those shells look like they’ve reached end of life!
Rob

 

[Skye 1872]

Images of my rod bearings removed today at 40,000 miles 12973707-C4DC-40B8-A50C-0A54D9B73AB0.jpeg

Some of those shells look like they’ve reached end of life!
Rob

Definitely needed doing
Just shows you’ve no idea how car has been driven by previous owners

 

[XMetal]

Definitely needed doing
Just shows you’ve no idea how car has been driven by previous owners

I don't think it matters. My car was mainly driven by me it's entire life and has been properly warmed up prior to romping on it, yet still required bearing changed at about 55k miles. But then again, I could be a really bad operator that caused the excessive wear

Glad you've decided to change it and keep it on the road for a long time!

 

[mmm-five]

Definitely needed doing
Just shows you’ve no idea how car has been driven by previous owners

I don't think it matters. My car was mainly driven by me it's entire life and has been properly warmed up prior to romping on it, yet still required bearing changed at about 55k miles. But then again, I could be a really bad operator that caused the excessive wear

Glad you've decided to change it and keep it on the road for a long time!

..and mine, driven quite hard on road ands track, lasted 140,000 miles (on the new engine) before they started making a noise

I’ve owned it since 9,000 miles, it had a new engine at 23000 miles under warranty, and it’s been over-serviced since then by a factor of 3 or 4.

 

[Mr Tidy]

Images of my rod bearings removed today at 40,000 miles

Some of those look pretty worn - you must be relieved you had them replaced!

I had mine done last year at 78,000 miles - and was glad I did.