5W-50 Recommended by TroyJeup

[Helmsman]

Originally Posted by Scharbag

These are my 088/089 bearings. They look good for an S65. They still show wear. And at 30K KM, that is just unacceptable. These are probably the best set of 088/089 bearings I have seen come out of an S65.

At best, the new 702/703 bearings have never looked excellent - just OK.

Perhaps if I am bored some day, I will take my BE bearings out for a quick inspection.

Haven't seen these before Scharbag, your shells look good! Another one replacing far too early, me included.

[Scharbag]

Originally Posted by Helmsman

Haven't seen these before Scharbag, your shells look good! Another one replacing far too early, me included.

Schrödinger's cat unfortunately.

No way to know unless you look. And if you are looking, you might as well replace.

Very happy that I know I have proper rod bearing clearance for a high performance engine. Hopefully I get many, many, many years of fun out of this V8 lump.

Cheers,

[Frozen]

I've made the switch to Redline 5w-50. If you look more at Troy's Instagram he's got some fairly compelling stories on this.

I live in a cold climate too. It's the cold start that I believe does the damage with the thicker OEM oil.

[Denny347]

Hell, I came here looking for an answer to the cold start clank. Was wondering if the 5W50 would be less inclined to clank for a second after the car sat for a week. Especially in winter months and near or below freezing temps.

[wfdeacon88]

Originally Posted by Denny347

Hell, I came here looking for an answer to the cold start clank. Was wondering if the 5W50 would be less inclined to clank for a second after the car sat for a week. Especially in winter months and near or below freezing temps.

If the cold start clank isn't a big deal, I would personally not change oil types outside of the factory spec.

[pbonsalb]

You could try it, but if the clank is from oil draining down because the car has not been driven for a week, then I think the lighter oil would also drain down.

[wyatth]

Not sure there’s any way around it but the cold start clank sure makes me cringe!

[kyippee]

Originally Posted by Scharbag

And one other thing: no one has spun a properly installed BE bearing from what I have read. So there is that too.

I have

[pbonsalb]

Was the spun rod bearing due to a failed main bearing?

[Scharbag]

Originally Posted by kpewpew

I have

As asked, did the mains fail first?

[Scharbag]

Originally Posted by Frozen

I've made the switch to Redline 5w-50. If you look more at Troy's Instagram he's got some fairly compelling stories on this.

I live in a cold climate too. It's the cold start that I believe does the damage with the thicker OEM oil.

There are ~70 Million engines made every year. All cars with reciprocating engines share the same fundamental rotating assembly. There is absolutely nothing special about the rotating assemblies in the S65 and S85. If cold start was a real issue, we would see far more engines failing as a result of cold start damage. Porsche, Ferrari, Lamborghini, Audi, Mercedes, Honda, Yamaha, Suzuki, Toyota Honda, Chev and Ford have all figured out how to build high performance daily driven engines that do not fail due to being started. This is because starting an engine is a low stress activity and the residual lubricating film of oil is capable of protecting the rotating parts from damage for the 1.5-2.5 seconds it takes to build flow and pressure. If starting an engine was that bad for it, more engines with the auto-stop feature would be failing as that has been available for many years now.

Changing the viscosity of the oil by a small fraction will not fundamentally change the overall results. People run redline 10W60, which is thicker than OE, without significant increases in wear and failure rates. Others run 0W40 without fundamentally changing the wear or failure rates.

The available data (part measurements and flow data) shows that there is a statistical chance that your S65 or S85 was built too tight. If that is the case, unicorn tears and angel blood will not protect your bearings.

Cheers,

[tdott]

There are also several stock s65 that made it to higher mileage on stock bearings, i think it was one at 285k that came to mind where it was bought by someone here and bearings were changed.

So the fact that an S85 running some snake oil miracle mix made it, means close to zero.

The issue is no one can tell you where that engine is on the tolerance stack until you open the engine, so you either don't believe in the data out there or you want to take a 10k+ risk. Others prefer to spend a bit and do the bearing to reduce that risk.

[pbonsalb]

Originally Posted by tdott

There are also several stock s65 that made it to higher mileage on stock bearings, i think it was one at 285k that came to mind where it was bought by someone here and bearings were changed.

So the fact that an S85 running some snake oil miracle mix made it, means close to zero.

The issue is no one can tell you where that engine is on the tolerance stack until you open the engine, so you either don't believe in the data out there or you want to take a 10k+ risk. Others prefer to spend a bit and do the bearing to reduce that risk.

I think Troy Jeup has a lot of experience with these motors, though much more with the S85 that has the same rod bearing issue. He might be onto something. 10W60 may be thick for street driven S65. And Redline by most accounts is a good oil. I would still change bearings if they are original, but I would consider 5W50 after the change. I have not run 10W60 for over 40k miles, since I changed bearings in 2014. Curious what they look like now. I was going to wait until I have 60k on them to change again since I changed the originals at 60k, but that could be 2-3 years at the rate I drive this car (I drive 2 other cars as well). And when I do change bearings again, I will go with increased clearance bearings - using the industry standard for clearance seems reasonable to me.

[kyippee]

Originally Posted by pbonsalb

Was the spun rod bearing due to a failed main bearing?

Originally Posted by Scharbag

As asked, did the mains fail first?

Hey guys,

I honestly don't know. Purchased car at 39k miles, done ~25-30 track days with it, had BE bearings + BE-ARP bolts installed about 6-8 track days and ~6k miles ago. Then it blew (overheat + rod knock on track) at 67k miles. Oil used in my ownership has been Castrol TWS 10w60, OE BMW (Shell) 10w60, Ravenol 10w60. When the motor blew it was on OE BMW (Shell) 10w60.

We inspected the motor. Engine oil filter was like a glitterbomb. Opened the bottom, we found bearing #1 seized to the crank. Didn't bother investigating any further because I didn't want to bother paying even more labor to open up the top and get deep in there.

Was considering a 4.6L stroker build but ended up replacing with a reman 4.0L motor. Put BE bearings and BE-ARP bolts in this new motor as well. Have 2,000 miles and 2 track days on this new motor now.

[Scharbag]

Originally Posted by pbonsalb

I think Troy Jeup has a lot of experience with these motors, though much more with the S85 that has the same rod bearing issue. He might be onto something. 10W60 may be thick for street driven S65. And Redline by most accounts is a good oil. I would still change bearings if they are original, but I would consider 5W50 after the change. I have not run 10W60 for over 40k miles, since I changed bearings in 2014. Curious what they look like now. I was going to wait until I have 60k on them to change again since I changed the originals at 60k, but that could be 2-3 years at the rate I drive this car (I drive 2 other cars as well). And when I do change bearings again, I will go with increased clearance bearings - using the industry standard for clearance seems reasonable to me.

I am unsure why 10W60 is considered too thick. I base this statement on the flow data provided by AutoTalent which clearly shows that with proper bearing clearance that there is adequate flow across the RPM range.

Of course, you need to not be running 8000RPM with cold oil. But for daily driving and normal use, there is no reason to think that the viscosity of the oil is the culprit according to the supplied measurements and data.

This chart, taken from AutoTalent's post, is what I am basing my statements on (plus all the other data available from BE and AutoTalent). It is clearly shown that with adequate clearance, proper oil flow can be established when using 10W60 oil.



The chart also shows that the OE clearance of the AutoTalent test engine was inadequate to allow for proper oil flow, especially above 8000RPM. As some of the professional engine builders have said, there is no way an engine can survive at 8000+ RPM with such low oil flow volumes.

In my case, I have BE bearings with BE-ARP hardware. I also run Redline 5W50 because it has a viscosity (21) and HTHS (5.0) that is very similar to the original Castrol 10W60 oil specified by BMW (22.7, 5.2). That said, I have run Castrol 5W50 Syntec (18.4, 4.1) in the past and it seemed just fine.

Cheers,

[pbonsalb]

10W60 probably is not too thick once it is hot, but maybe 5W50 flows better during warm up or flows better when clearance is on the tight side of stock specs.

[Scharbag]

Originally Posted by pbonsalb

10W60 probably is not too thick once it is hot, but maybe 5W50 flows better during warm up or flows better when clearance is on the tight side of stock specs.

That I can agree with yes. But I still think that there is no magical oil that can make up for lack of clearance. Fix the problem then use good oil of your choosing.

[tigermack]

I had to... lol

[akkando]

Originally Posted by kpewpew

Hey guys,

I honestly don't know. Purchased car at 39k miles, done ~25-30 track days with it, had BE bearings + BE-ARP bolts installed about 6-8 track days and ~6k miles ago. Then it blew (overheat + rod knock on track) at 67k miles. Oil used in my ownership has been Castrol TWS 10w60, OE BMW (Shell) 10w60, Ravenol 10w60. When the motor blew it was on OE BMW (Shell) 10w60.

We inspected the motor. Engine oil filter was like a glitterbomb. Opened the bottom, we found bearing #1 seized to the crank. Didn't bother investigating any further because I didn't want to bother paying even more labor to open up the top and get deep in there.

Was considering a 4.6L stroker build but ended up replacing with a reman 4.0L motor. Put BE bearings and BE-ARP bolts in this new motor as well. Have 2,000 miles and 2 track days on this new motor now.

BE bearings and it blew up after 6k miles. That's concerning and scary!

[Rcase]

I ran Redline and also Joe Gibbs when Driven when I lived in Illinois. I firmly believe that both are a substantial improvement on the S65 and S85. Once I put fresh bearings in our M5 and M3 I will switch again.

[Rcase]

Originally Posted by akkando

BE bearings and it blew up after 6k miles. That's concerning and scary!

Not stating the builder did not perform their job correctly, however after installing and building many engines the past 20 years any engine will seize if not properly put together. We do not know if they just slapped in a set of BE's without checking tolerances.

[tdott]

Originally Posted by akkando

BE bearings and it blew up after 6k miles. That's concerning and scary!

Most likely main bearing went first.