Rod Bearing Break-in (hint: there isn't a need)

[jbfrancis3]

Engineer here. These are hydro-dynamic bearings, meaning they rely on a high film strength in oil in order to lubricate the surface. No metal-to-metal contact should occur.. with that said, I recently changed my bearings with VAC moly-disulfide coated bearings and followed a break-in procedure of 1200 miles of no full throttle, no rev's past 4.5k. After that, I changed the oil again, and now have peace of mind. Is this necessary? probably not, but well worth it in my mind.

Did you opt to check clearances with plasti-gauge?

[JayVee]

Engineer here. These are hydro-dynamic bearings, meaning they rely on a high film strength in oil in order to lubricate the surface. No metal-to-metal contact should occur.. with that said, I recently changed my bearings with VAC moly-disulfide coated bearings and followed a break-in procedure of 1200 miles of no full throttle, no rev's past 4.5k. After that, I changed the oil again, and now have peace of mind. Is this necessary? probably not, but well worth it in my mind.

[IamFODI]

And according to post #56, BMW dealerships no longer demand the old break-in period after replacing S54 rod bearings.

True, but nor do they have a full factory warranty commitment to deal with. Just the 2 years on the repair, no?

[Jimbo's M]

Well to be fair all the tens of thousands of us during that campaign were under warranty too.

I was replying to members on this forum that may not have gone through this, not the original owners of the whole planet. I'm quite sure there can't be more than a handful here that have had original warranties, so I made the comment. Nothing more, nothing less. If all the hoops I jumped through were essentially meaningless, now after 19 years, I'll get over it.

[old///MFanatic]

Easy to just to forget what the dealer said except for one tiny detail in my case, I was still under full warranty even after the second bearing change. Doesn't matter what I think, doing it their way three times was brutal. So, the way I see it is either you do their way or face something effin' up that I would be liable for because the DME or whatever fibbed on me.

Well to be fair all the tens of thousands of us during that campaign were under warranty too.
I don’t think anyone is denying what the policy was from BMW then. I think the thread is about current policy or need for break-in. And according to post #56, BMW dealerships no longer demand the old break-in period after replacing S54 rod bearings. Which follows other major respected shops like Lang Racing who don’t have a break-in rod bearing requirement. Nor a soon after oil change.

[IamFODI]

Getting a bit spicy in here. Let's drink some milk / eat some rice and get back on topic.

[Jimbo's M]

BMW gave the specs to the mfg, including the acceptable tolerances. then either accepted the out of spec parts that were delivered or didn’t care enough to do a final check prior to or during assembly.

Like I said, not making excuses. Just having a conversation...

[tnord]

BMW gave the specs to the mfg, including the acceptable tolerances. then either accepted the out of spec parts that were delivered or didn’t care enough to do a final check prior to or during assembly.

[Jimbo's M]

you’re right, BMW has a great reputation for putting out reliable engines with no bearing issues whatsoever. how dare i question them.

Not positive nor an excuse, but I believe BMW contracted bearings out.

[Jimbo's M]

This is one of my favorite type of fallacies.

Then educate us.

[tnord]

If you guys are so smart about bearings, why don't you give BMW M engineers a ring and tell them they're full of shit. I'll watch.

you’re right, BMW has a great reputation for putting out reliable engines with no bearing issues whatsoever. how dare i question them.

[jet_dogg]

If you guys are so smart about bearings, why don't you give BMW M engineers a ring and tell them they're full of shit. I'll watch.

This is one of my favorite type of fallacies. Reminds me of the shitty job coaching Dave Roberts does for the Dodgers and geniuses in the comments will say "oh well how come you're not a coach then!" etc haha.

[old///MFanatic]

Genuine question, is changing the oil not part of the procedure?

Nope BMW states directly in regards to the Rod Bearing Campaign, “Engine oil service is not required after completion of engine break in period”. I posted this document section in post #52.
There is also no code given to pay for a 1,200 mile oil change after this procedure. Nor did we get a notice for one. We did get a full tank of gas, car washed and valet service even covered by BMW. BMW dealerships were given all those codes for reimbursement.

New ENGINES are different. Yes oil change service ~1,200 miles.

[Chanman1029]

The BMW break in procedure is about rpms for a particular period (miles), not oil.

Genuine question, is changing the oil not part of the procedure?

[Jimbo's M]

Easy to just to forget what the dealer said except for one tiny detail in my case, I was still under full warranty even after the second bearing change. Doesn't matter what I think, and trust me, doing it their way three times was brutal. So, the way I see it is either you do their way or face something effin' up that I would be liable for because the DME or whatever fibbed on me. If you guys are so smart about bearings, why don't you give BMW M engineers a ring and tell them they're full of shit. I'll watch.