BE Bearing Longevity?

Okay, I'm new to this forum but I've read enough to see that people are likely tired of discussing rod bearings. But I have some questions I don't think I've seen answered anywhere on the forums.

I bought a 2013 M3 Convertible about 3.5 months ago. When I bought the car they gave me receipts showing that the bearings were replaced @ 35,000 miles by the previous owner in 2019. It has 82,000 on it now. I didn't call the shop to verify which I would've done now probably, but I don't have any reason to believe the receipt is fake.

I just had the throttle actuators done by the dealer as well as the coils & engine oil replaced after I had driven the car 3,000 miles. I intend to replace the engine oil every 3,000 miles, even if that seems too soon, just for my own piece of mind. The car is in really nice shape and the last thing I want to do is be the person that turns it into a sh*tbox, although the service advisor told me that all the techs were complimenting on how nice my car was.

Anyways, on to what I wanted to ask. Regarding the BE bearings, from what information I've gathered online, the consensus is that when you replace them with those you don't ever have to worry about rod bearings again. Now that the car has put on almost 50,000 miles since the replacement, I'm wondering whether I should pay to replace them again. If anything I'm really curious how they've held up after 50k miles.

Occasionally ill hear what I think is a strange noise. The exhaust tick on cold start and low RPM throttle spooked me for a bit but I learned that was normal. I know that the S65 is a noisy engine in general. That sort of makes me wonder if the RB's were to start making a subtle noise that it might be difficult to catch.

I may come off as paranoid asking this, and perhaps I am (I'm being completely candid, every time I start the car I listen to the engine to make sure I don't hear any strange noises before I shut the door) but I figure its best to know all the info I can because nobody wants to be on the wrong side of a bad engine. I drove the car 200 miles from middle Virginia back up to Northern Virginia and the car seemed to handle it no problem. Unfortunately the actuators died on me while I was down there and had to leave the car down there as the dealer gave me a loaner 5 series (that's a whole other story). I think that whole mess with that reignited my fears of catastrophic failure even though I obviously know the TA's have nothing to do with RB's, but nevertheless.

More than likely if the worst case scenario happened and a main bearing or somehow the BE bearings failed I would likely have the car sit for a few months and save to do a Carbahn (Dinan) 4.6 stroker rebuild. If that were to happen and I'm paying a proper amount of money to mend it, I might as well make it better, right? Even if the bearings don't fail my next goal is likely to save for that anyway. Anyways, I digress.

But I'm interested to hear from anyone regarding anything. Again, I'm being honest, since I've spent not that much time with the car despite putting over 3,000 miles on it so far (I've been driving it almost everyday since I bought it) I'm still a little of afraid of the worst case scenario occurring so soon. I know there are some people that won't admit being paranoid but I openly am. Although I wasn't a total dumb dumb and I made sure after the purchase I had more than enough money to stomach almost anything. That doesn't mean I want to wait until anything fails however.

I'm not going to let my anxiety win though, I'm already in love with the car and can't imagine being without it

I did ask a few year back and no seller was able to guarantee me that BE bearings are lifetime. There's currently insufficient data on how much longer BE - or any other aftermarket bearing - lasts. For those reasons alone I have stuck with stock bearings.

The s65 has a lot of clicks and ticks and various other sounds. If you hear a noise and your car still goes, it’s not the rod bearings.

There’s not enough data for anyone to provide anything but an opinion. We’ve not seen very many failures on aftermarket bearings but most people are just getting to the 40-60k point on their aftermarket set. I’ve also not heard of many folks choosing to do a second round of rod bearing replacement. Given the uncertainty, I’m personally choosing to replace my VAC bearings after 60k+ supercharged miles with a set of BE bearings next month.

I'd be more nervous about the main bearings that you can't realistically replace.

nrubenstein wrote

I'd be more nervous about the main bearings that you can't realistically replace.

do they even make higher clearance main bearings for this block? just thinking if i ever went down the stroker path if that would even be in the cards.

BE bearings is a once and done kind of replacement. Maybe at extremely high mileage you may want to replace the bearings? But by then you may just want to do a engine rebuild given everything else is worn down.

You say you want to do a 4.6 rebuild if the rod bearings go? If your bearings go, you can end up with a hole in the side of the engine. Not to mention the damage to the engine from having things explode internally. Catastrophic engine failure is... catastrophic. There's no way to rebuild that. For a stroker build, you'd want a block that is from a well running engine.

My E92 had the rod bearings done with VAC bearings at 146K by the previous owner. The motor has yet to blow up at 205K.

There is no long term concern with BE or any other replacement rod bearing with the proper clearances. It's considered a one-time need. The main bearings in the engine will fail before new rod bearings will.

In my personal experience inspecting BE extra clearance bearings after about 50,000 miles and ACL extra clearance bearings after about 18,000 miles in an engine that always ran 10w60, neither had any visible wear at all.

Theodore2 wrote

In my personal experience inspecting BE extra clearance bearings after about 50,000 miles and ACL extra clearance bearings after about 18,000 miles in an engine that always ran 10w60, neither had any visible wear at all.

Nice input Theo. Does one put the engine(s) back together with the same shells when they turn out to be untouched?

Btw, do you know if the ACL was extra clearance (HX) only, or mixed?

OP - welcome onboard!

Helmsman wrote

Nice input Theo. Does one put the engine(s) back together with the same shells when they turn out to be untouched?

Btw, do you know if the ACL was extra clearance (HX) only, or mixed?

From my point of view, with no visible wear, there is no need to replace them. The ACL bearings were from a single factory box of extra clearance only (HX), it was not one of those mixed sets I've seen advertised by some retailers.

Theodore2 wrote

From my point of view, with no visible wear, there is no need to replace them. The ACL bearings were from a single factory box of extra clearance only (HX), it was not one of those mixed sets I've seen advertised by some retailers.

Thanks again mate. Always interesting to read about shells coming out unworn (vs the tons of worn we've seen...), guess you didn't snap a couple of pics, or did I miss them?
Happens to run ACL HX myself since a few years. Should I keep the car (which I suspect I do after the first 10 years...), I may have the shells replaced again in the future. Probably BE v2 that day, but till then I'm grateful that the ACL' does the job.

Helmsman wrote

Thanks again mate. Always interesting to read about shells coming out unworn (vs the tons of worn we've seen...), guess you didn't snap a couple of pics, or did I miss them?
Happens to run ACL HX myself since a few years. Should I keep the car (which I suspect I do after the first 10 years...), I may have the shells replaced again in the future. Probably BE v2 that day, but till then I'm grateful that the ACL' does the job.

No pictures, sorry, but literally no wear, not even the light outer layer wear you see on even on the cleanest factory bearings that people post pictures of on here.

deansbimmer wrote

There is no long term concern with BE or any other replacement rod bearing with the proper clearances. It's considered a one-time need. The main bearings in the engine will fail before new rod bearings will.

Thanks Dean! Follow up questions:

1) Is it a given that our main bearings will all fail and if so, is the mileage at which this will happen predictable?

2) Are there any preventative measures that can be taken to avoid or prolong such a failure?

Thanks in advance.

Nickco43 wrote

My E92 had the rod bearings done with VAC bearings at 146K by the previous owner. The motor has yet to blow up at 205K.

Wow, that is the highest mile S65 I think I’ve ever heard of.

I think the solution is for me to just drive the car and stop reading the forums the thing is I’m just an anxious person. I worry about everything and it’s hard for me to let go. I guess one could argue I purchased the wrong vehicle then.

From what I’ve seen it’s about 7k for a used engine. I know a new long block S65 is about 25 grand, and the dealer would probably want another 10 to put it in. I don’t really like the idea of a used engine because I don’t want to spend ~15 grand to go that route just to have the engine grenade again shortly thereafter. But again, I think the solution is simply for me to simply chill the f*k out.

I feel like I spend more time worrying about it than enjoying it or driving it. I’m not comfortable even driving it on the freeway anymore. I wasn’t that concerned until the TA’s went bad while I was 3 and a half hours away (I know the TAs have no correlation to the bottom end whatsoever) and since that’s a common failure I’m worried I’m going to get the other common(ish) failure (at least if you spend too much time on here): complete engine failure.

When I get be bearings I will probably never replace them. I do plan on keeping my car forever.

You could chalk it up as a maintenance expense every 30K miles if you want, lol. But you should be fine.

The only recent documentation of a bearing failure was done via SpeedAcademy on YouTube. However, if you watch that video, it's inconclusive as to the reason for the failure. It seemed more like an oil starvation issue or main bearing failure before anything else.

The BE bearing fix the issue the OEM bearings had. In theory it shouldn’t require much more attention though you could consider it preventative at 100k or whatever interval you seem fit.

omgzirra_exe wrote

You could chalk it up as a maintenance expense every 30K miles if you want, lol. But you should be fine.

The only recent documentation of a bearing failure was done via SpeedAcademy on YouTube. However, if you watch that video, it's inconclusive as to the reason for the failure. It seemed more like an oil starvation issue or main bearing failure before anything else.

I saw that video being discussed on here. I find it suspicious it failed so soon after he installed those VAC bearings (4k km = ~2400 mi). I was reading the comments of his video where he inspected the bearings and people said that the VAC bearings had a coating that made the tolerances too tight. He apparently also didn’t measure the tolerances before installing the bearings. Not sure.

ewartim3 wrote

I saw that video being discussed on here. I find it suspicious it failed so soon after he installed those VAC bearings (4k km = ~2400 mi). I was reading the comments of his video where he inspected the bearings and people said that the VAC bearings had a coating that made the tolerances too tight. He apparently also didn’t measure the tolerances before installing the bearings. Not sure.

vac bearings are overside also made by mahle to there specs

BE bearings should last until your main bearing 1 goes.