What’s one thing S54 owners worry about? That’s right, rod bearings: Are they good or are they about to fail and wipe out the entire engine?
[E46-chassis BMW M3 | Buyer's Guide]
Gulp.
We’ve had this in the back of our mind ever since we bought our 2004 BMW M3. Even though the car sported plenty of documentation, was built after BMW’s mid-run update, and came from an old friend, we didn’t know the history of its rod bearings.
The odometer showed 138,000 miles. Surely they had been done at some point, right? (Right?)
That was the one question mark always hanging over this car. And, we admit, it kept us from fully enjoying it. It’s hard to spin a rather pricey, 8000 rpm engine to the redline when you’re unsure about its health.
Oil analysis and physical inspections didn’t reveal any looming trouble, either–no warning signs, no noises. Still, we felt it was time to replace those rod bearings.
A lot of the info found on the internet regarding E46 M3 rod bearings seems to have been posted at least a decade ago, however, so we asked James Clay, president of BimmerWorld, if there was anything new to report.
James has been our spiritual guide for this project, from initial inspection to countless late-night texts. Plus, he knows BMWs and has owned more than one E46 M3.
During the E46 M3’s model run, there was a production split: pre- and post-recall. “It was considered the solution,” he says.
“What we know with certainty now is that S54–and similar engines found in the future models, the S65 and S85–need rod bearing attention as part of general maintenance, recall or not,” he continues.
“Rod bearing issues are more prone to affect higher-load engines–something routinely revving over 7000 rpm.” He says this discussion should also extend to later BMW engines like the S65 and S85, and he expects it to also impact modern, big-boost engines like the N54, N55 and S55.
“A majority of wear is caused in startup and warmup,” he explains. “Properly warming up your engine seems to notably reduce bearing wear.
“A proper engine oil with high sheer strength–I look for a Group V full-synthetic, PAO-ester base like Red Line–will help on both startup and high revs.”
More questions for James: Are there any signs for when it’s time to replace the bearings, and can an oil analysis help?
“One oil analysis can’t help,” he explains, noting that “a trend over a span of time and seeing the trend suddenly change can. On the street, I’ve heard them make rod noise before they damage the crank, but that’s a small window. And on the track, you likely don’t get that warning.
“That being said, it’s about $800 of parts for a premium bearing and oil, or a $2000 job at full pop with labor, and I feel like if you’re going to own one of these cars, you just plan on it at some point.”
How often should you replace rod bearings? “For a road car,” he says, “if I bought one with over 70K miles and it wasn’t already documented as being done, I would inspect and/or do them. If I bought a car from myself with scheduled oil changes with Red Line and a proper warmup on the engine before driving, I’d feel very comfortable with 100,000 to 120,000 miles before looking at them–not that I put that many miles on these cars.
“And I guess that’s the real thing: At this point, I don't know that many people intend to stack miles on these cars, so doing it once when you get it for peace of mind for the duration of ownership is probably worth it.
“I do treat track cars differently, because when an engine goes at the track, it’s going to go fast and it’s going to be at least a full engine replacement typically, if not some additional damage due to dropping oil in that environment–for yourself or, even worse, for others.
“I never ever pass up an opportunity when an engine is out of the car or the oil pan is accessible to take a look at the rod bearings. I may not always replace them, but I take a look and replace the rod bolts. Then I like to replace them every two years or 100 hours or so on full-race engines. They can likely go twice as long or more–again, with the right warmup and the right oil–but the risk of damage is just too high to not be more proactive.”
Our car was built after the 2003 update. Does that matter? “Nope,” James tells us. “Or it matters minimally. It was, in effect, a great way to put new bearings in cars–on the update–to get them further down the road.
“Just like the reason you’re asking about two flavors of S54–and I’m saying those flavors don’t matter–and what does are the revs. The ’03 update is minutiae.”
Driving style matters, he stresses: “The real issue is people jumping in cars and putting the throttle down, and maybe to some degree doing the included maintenance thing–not sure when that started–but definitely not using the premium oils.
“Take care of the car,” he continues. “BMW put in the dynamic rev indicator lights so when the car is cold it shows yellow lights around 5K rpm to limit people from pounding on the car when cold–and when most damage occurs.
“That is not enough. To me, aside from using a high-sheer-strength oil like Red Line or some other true Group V base, warming the engine means a good 3 to 5 minutes at idle after starting. Then I don’t pay attention only to rpm or that moving rpm yellow limit light. I care more about load I put into the engine, so I keep throttle below 30% to 50%, and I definitely keep rpm below 3000 to 4000 rpm until I hit about 170 Fahrenheit. Then I start leaning into it.
“That means I don’t drive these cars when I’m late to work, but I think for most people that’s not the use of these cars anymore anyway. They are special. Take your time. They’ll appreciate it.”
Phil Wurz, BimmerWorld’s sales and operation manager, notes how each engine is unique. “Not to cause alarm to the hundreds of thousands–millions?–of N55 engines that are found in so many BMWs. I did rod bearings on my wife’s X5 at about 165K miles, and they had a little wear but were in decent shape,” he says.
“If I had a crystal ball, I wouldn’t have changed them, but really I was just curious,” he continues. “Of course, this is a car that rarely sees over 4500 rpm. Also, while we didn’t buy it new, under our ownership it has followed the standard BimmerWorld practice of a Red Line oil and to properly warm the car up in the winter.
“On the other side,” he continues, “our F82 M4 GTMore project car with an S55 engine seemed to have a track-abused life before we got our hands on it. It was unknown how many track miles it had, but we know the odometer showed over 50K. We did bearings preventatively and, sure enough, there was some copper showing on the bearings.”
Spoiler alert: We finally decided to replace the rod bearings. As James stresses, it’s part of the ownership experience, and you can only kick that can so far down the road.
We figured that you get one shot at this job. Mess it up and, well, now you’re looking at an engine rebuild–or worse–and these engines aren’t exactly common.
We wanted to have an expert do the work.
Fortunately, the engine doesn’t have to come out of the car for this service. The front subframe must be dropped so the oil pan can be pulled, but the entire procedure can be done from below: Remove bearing caps, remove bearings, replacing bearings, fit new rod bolts, torque to spec, reassemble everything.
While in theory the front suspension will go back together as it was, we were advised to get an alignment afterward.
[Fresh Red Line Fluids for Our High-Revving M3]
We called a few local BMW shops, and they were too busy or just not interested in the job. Rennie Bryant at Red Line Bimmer Performance said his shop regularly replaces rod bearings, but South Florida is a bit of a hike from our home base near Daytona Beach.
Sometimes the answer is hiding under your nose. Auto Clinic of Ormond has been servicing our staff’s cars for years–project cars and just regular cars–and has done this job before.
In fact, the shop had recently done another S54 engine. It’s located about 10 minutes away, so the folks there put us on the schedule.
Now to gather parts.
We turned to BimmerWorld for our parts order, and the shop recommended rod bearings from BE-Clevite. “A few years back, the BE Bearing option came onto the scene,” Phil explains. “The issue they were trying to remedy with their bearing solution was to open up the tolerance relative to the BMW bearings.
“The BMW bearings have always been a bit on the tighter tolerance side versus some others, so that factors into the wear rate of the bearings to a certain extent,” he continues. “The BE Bearings making the tolerance just a touch larger helps improve the lifespan of the bearings. The BE Bearings also have a coating on them to help in low oil–initial startup–and clearance scenarios, and they’re also a tri-metal shell design that can handle much higher loads to withstand the abuse of the higher-revving S54.”
A set retails for about $400.
Where you buy bearings–and, really, any other critical parts–also matters. As Phil tells us, BimmerWorld has rejected bearings from another supplier that didn’t pass muster. That company’s warehouse, located near the coast, supplied bearings sporting some surface rust. Those bearings were turned away.
What about our main bearings? Something else to worry about? No, James says.
“To me,” he says, “mains aren’t an inherent wear issue. Off the cuff, rod bearings are replaced 10:1 over mains, and most mains that get replaced are ‘while you’re there.’ But if you ever see a damage pattern indicating trash went through the oil passage when replacing the rod bearings, it’s worth a peek at the mains also.”
We also needed rod bolts. BimmerWorld says that the ARP pieces are 10 times stronger than the stock ones, so that’s what we ordered.
The ARP catalog shows two different part numbers for the S54 engine, however. As ours was built after February 2003, we’d need ARP part No. 201-6102–about $113 from BimmerWorld.
The rest of the job doesn’t need much regarding parts: just an oil pan gasket, oil filter and a few quarts of Red Line Oil. Like the bearings and bolts, these parts can also be found in the BimmerWorld catalog. (By the way, BimmerWorld carries Red Line for non-BMWs, so it has 10W30 for your Miata.)
We dropped off the M3 at Auto Clinic on a Monday morning. Its technicians said we’d see the car by the end of the week.
“End of the week” must mean “end of the next day” in their world. Even while stopping so we could take photos, they had the car ready for us by EOD the following day.
A casual look showed that the bearings didn’t appear too worn. No copper showing through.
Could they have gone another 10,000 miles? We guess the answer depends on how much you like to gamble.
The inside of the engine looked just as clean as the outside. No issues at all were found during the service.
While the car was there, we also had Auto Clinic replace the VANOS line with an upgraded piece from BimmerWorld. After a while, these lines can weep a bit.
The work order shows that replacing the rod bearings took 12 hours. Multiply that by your shop’s hourly rate to get an idea for a likely bill. In very round numbers, like James says, this was a $2000 service once adding in the price of the bearings, rod bolts, oil and gaskets.
When we bought our M3, it was a $10,000 car. Today, well, you can easily double that figure for an example this clean. And at the rate we drive the car, the bearings are now good for a decade or three.
One last step to complete the job: After getting some gas as advised, we took the car back to Alignment Shop, Inc., for an alignment–same specs as before.
So what’s next for our BMW M3 now that we’ve addressed two of the big three issues with these cars–subframe mounts and rod bearings? How about we drive it and enjoy it?
Next, though, we should take a closer look at the third item on that list: the VANOS system.
Hello, BimmerWorld, mind a little more hand-holding?
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Comments
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I think one of the MOST important points on this article is the warming up of the engine. I myself never let it sit for that long, but drive it extremely slow, under 2k rpms for about two miles and then dont go over 3 until the oil gets to temp.
Luckily these cars have an oil temperature gauge. If you use the water temperature gauge as a guide, you would be fooling yourself into thinking the engine is at operating temperature when its really not. It takes a long time for the oil to come to temperature, probably a good 7 miles.
This is my engine after a good 3 miles. You can see how the coolant is all warmed up while the engine oil is not:
My bearings after 98k miles, granted there are quite a few track miles on them at this point.
You can diy this job easily for about $600. I spent around $1500 and did all new front suspension, gaskets, motor mounts, etc. Those are all easy while in there jobs.
I used WPC treated factory bearings. We'll see how they did in 50k miles.
Slippery said:
I think one of the MOST important points on this article is the warming up of the engine. I myself never let it sit for that long, but drive it extremely slow, under 2k rpms for about two miles and then dont go over 3 until the oil gets to temp.
It's my understanding that you should do this regardless of what you drive (especially when it's really cold out).
I don't have the resources or findings to back up this claim, but being a little extra careful can't hurt, right?
I agree with not beating on any engine until it's good and warm. Full oil temp will usually be a good 5 minutes after full coolant temp. And on most BMWs, the coolant temp gauge shows "normal" over a pretty wide range. So it's usually 3 - 5 minutes from when the gauge hits center to when the coolant is really up to temp. Meaning for BMWs without an oil temp gauge, wait closer to 10 minutes after the temp gauge hits the center before beating on it.
I bought my M3 with 93K on it and unknown bearing history. Since it was intended to be a race car I did the bearings immediately, they definitely needed it although none were as bad as Slippery's #5. Worse than his #1 though.
100 track hours later (around 7-8K miles) it was time again, they looked like this:
OEM bearings, all hard track use, albeit always with redline oil and always warmed up. Yeah, they're a consumable maintenance item.
In reply to codrus (Forum Supporter) :
Ignoring race miles, if you use a 100k mile interval, even at $2k is not a lot of money per mile as piece of mind insurance.
And yes, I agree about always warming up any and all cars. I guess my point was more to not go by the water temperature gauge, as its diceiving.
In reply to Slippery :
You're right, that's not crazy insurance.
The biggest thing was finding a local shop to do the work. Did I really need to drag the car hundreds of miles to get the job done? And why wouldn't our local BMW shop do the job?
I had a few people recommend a shop an hour away in Orlando. I talked to the owner, and he was a GRM fan. One catch: They're only working on their race effort, so no outside jobs.
Womp, womp.
Tim recommended the stop that finally did the work. Being able to drop off the car and then bike home was huge.
wspohn
SuperDork
11/21/22 1:21 p.m.
My S54 engined car doesn't even have a proper coolant temp gauge, just a lit sector above the tach that indicates warming progress without numbers. I use the oil temp gauge exclusively to govern when I feel confident in being able to run the engine up the rpm range.
I have used oil temp gauges in my race cars for decades and feel kind of abandoned without sufficient information when I don't have that in a street car; BMW is the only one I have owned that has oil temp indicated.
In reply to codrus (Forum Supporter) :
Your picture didn't come through.
Slightly off- topic: Has there ever been an explanation on why this seems to affect the high-output BMW engines more than the Japanese manufacturers, or is it just in how it's reported?
CAinCA said:
In reply to codrus (Forum Supporter) :
Your picture didn't come through.
Hm. It comes through for me on various desktop browsers (what I normally use), but when I look at it on my phone it's missing. That's weird.
Parker with too many Projects said:
Slightly off- topic: Has there ever been an explanation on why this seems to affect the high-output BMW engines more than the Japanese manufacturers, or is it just in how it's reported?
I have read speculation that the root of the problem is the width of the bearings. It is highly desirable for BMW to keep the engine as short as possible since it's a longitudinally mounted inline 6, and adding bearing width increases the length of the engine, weight of crank, weight of cams, etc. Most 8K+ Japanese engines are Honda inline 4s, which changes things significantly.
The rapid wear in the track use example makes me think that either the oiling system is inadequate and can't maintain a sufficient oil film in the bearings or the bearings are just too small for the load being applied and no reasonable oil quantity/pressure and viscosity to the bearing will be sufficient.
codrus (Forum Supporter) said:
Parker with too many Projects said:
Slightly off- topic: Has there ever been an explanation on why this seems to affect the high-output BMW engines more than the Japanese manufacturers, or is it just in how it's reported?
I have read speculation that the root of the problem is the width of the bearings. It is highly desirable for BMW to keep the engine as short as possible since it's a longitudinally mounted inline 6, and adding bearing width increases the length of the engine, weight of crank, weight of cams, etc. Most 8K+ Japanese engines are Honda inline 4s, which changes things significantly.
I seem to remember that the 2003.5+ S54s have wider bearings. I have a 2004 M3 and also a 2002 engine, but I have not taken the early engine apart to check. They definitely use different bolts, the early ones are reusable and the later ones are not.
The width problem is real, but whenever you spin engines this high, bearings will become consumables. The Honda S2000 suffers from the same issue with rod bearings, albeit no as bad.
You guys are running a 10w-60 weight Group V oil in those S54 motors, correct? A good friend with one of those said something about "distilled from the tears of Bavarian woodland elves". On a serious note, I have to follow a similar warm up procedure with a built LS engine, that due to specific bearing clearances requires 15w-50 oil all the time. Takes awhile to warm it up to 170 degree, so the oil temp reading is up on the DIC at the times.
In reply to deaconblue :
I use BMW 10w60, yes. Not sure whether its Group V or not.
I might switch to the Redline version to test it out.
I do have Blackstone check at every oil change, usually 4500 miles, and they said that it remains a 10w60 at those intervals. I used to change it around 7500 and the oil was not happy.
Mine gets Redline 40WT race oil (which is not the straight-weight oil that the name would imply). It's a race car though, no street driving.
Slippery said:
In reply to deaconblue :
I do have Blackstone check at every oil change, usually 4500 miles, and they said that it remains a 10w60 at those intervals. I used to change it around 7500 and the oil was not happy.
Very good point, how long does the HTHS value last before it starts breaking down.
aw614
Reader
11/21/22 3:27 p.m.
codrus (Forum Supporter) said:
Parker with too many Projects said:
Slightly off- topic: Has there ever been an explanation on why this seems to affect the high-output BMW engines more than the Japanese manufacturers, or is it just in how it's reported?
I have read speculation that the root of the problem is the width of the bearings. It is highly desirable for BMW to keep the engine as short as possible since it's a longitudinally mounted inline 6, and adding bearing width increases the length of the engine, weight of crank, weight of cams, etc. Most 8K+ Japanese engines are Honda inline 4s, which changes things significantly.
Does that also apply to the high revving BMW V8s with similar bearing issues?
Slippery said:
codrus (Forum Supporter) said:
Parker with too many Projects said:
Slightly off- topic: Has there ever been an explanation on why this seems to affect the high-output BMW engines more than the Japanese manufacturers, or is it just in how it's reported?
I have read speculation that the root of the problem is the width of the bearings. It is highly desirable for BMW to keep the engine as short as possible since it's a longitudinally mounted inline 6, and adding bearing width increases the length of the engine, weight of crank, weight of cams, etc. Most 8K+ Japanese engines are Honda inline 4s, which changes things significantly.
I seem to remember that the 2003.5+ S54s have wider bearings. I have a 2004 M3 and also a 2002 engine, but I have not taken the early engine apart to check. They definitely use different bolts, the early ones are reusable and the later ones are not.
The width problem is real, but whenever you spin engines this high, bearings will become consumables. The Honda S2000 suffers from the same issue with rod bearings, albeit no as bad.
The width issue is real. S54s have the same bore spacing as the M20s in E30s. Which is why you can use an S54 crank to build a stroker M20.
So you have rod bearings designed to handle 167hp and 6k rpm, needing to handle 333hp and 8k+ rpms. I think Keith has pointed out the math before about how the load ramps up more with RPMs vs something like boost.
In reply to aw614 :
Yes, they use the same bearings. Actually the early S65s are made of a material that makes it hard for people like Blackstone to be able to tell you when things are going south.
I have 110k miles on my S65 e92 M3. Have been thinking of doing the bearings on that car more and more.
In reply to z31maniac :
On the flip side, you can say that the M20 is overbuilt 
I am using an M54B30 crank on my M20 stroker. Need to check the bearing widths on that crank to see if they are the same as the S54.
In reply to Slippery :
Can E92 M3 bearings also be changed from below?
In reply to David S. Wallens :
Yes, same process as the e46. I contemplated doing a few weeks ago when I did the clutch and the transmission was out but did not have the parts.
The M5 V10 version also has the same trouble. Search up the M539 video where he did his. There is a chunk he does in the middle that is particularly amusing, while wearing a fake mustache and doing a bad German accent.
Interesting.
Can you bump up the oil pressure a bit to increase the life of the rod bearings?
Noddaz said:
Interesting.
Can you bump up the oil pressure a bit to increase the life of the rod bearings?
Generally the oil pressure in the system had little to no relation to the film pressure on the bearings. If it's an oil supply issue then it might help a bit, but if it's the bearings themselves, then no amount of oil pressure will help.
Berck
Reader
11/21/22 11:33 p.m.
Just... how is it that anyone finds it acceptable that any car built in the last 20 years wears out rod bearings faster than most cars wear out timing belts?
Berck said:
Just... how is it that anyone finds it acceptable that any car built in the last 20 years wears out rod bearings faster than most cars wear out timing belts?
Have you driven one? They're worth it. How many 20-year-old naturally aspirated engines make over 100 hp per liter at the wheels with nothing more than a header, exhaust, and a tune?
In reply to David S. Wallens :
Race cars need dry sumps. Oil once it is hot is going to go away from the pick up and leave it sucking air. ( air is a lousy lubricant) Especially now that brakes are so excellent.
Baffles and accusumps. Simply delay but don't eliminate the running dry problem.
Back in 1954 Jaguar figured that out and every racing Jaguar since then has had dry sumps. It's also why they won LeMans so often. Where dry sumps were banned tricks like putting oil coolers in the rear of the car to counteract running dry under hard braking.
codrus (Forum Supporter) said:
Berck said:
Just... how is it that anyone finds it acceptable that any car built in the last 20 years wears out rod bearings faster than most cars wear out timing belts?
Have you driven one? They're worth it. How many 20-year-old naturally aspirated engines make over 100 hp per liter at the wheels with nothing more than a header, exhaust, and a tune?
Unless it's a plot by Big Rod Bearing, it's just a fact of ownership. On a new car purchase, I can see that fact stinging. Now, we know so going in.
ddavidv
UltimaDork
11/22/22 7:47 a.m.
Berck said:
Just... how is it that anyone finds it acceptable that any car built in the last 20 years wears out rod bearings faster than most cars wear out timing belts?
What he said.
Defenders of the Sacred Roundel seem to accept this as part of life but to me it's simply piss poor design. Couple this to all of the other things that fail on the E46 platform and you can keep 'em for yourself.
ddavidv said:
Berck said:
Just... how is it that anyone finds it acceptable that any car built in the last 20 years wears out rod bearings faster than most cars wear out timing belts?
What he said.
Defenders of the Sacred Roundel seem to accept this as part of life but to me it's simply piss poor design. Couple this to all of the other things that fail on the E46 platform and you can keep 'em for yourself.
Lol
In reply to codrus (Forum Supporter) :
Actually, Honda has reduced rod bearing widths over the years.
That goes for the higher output motors as well as grocery getters.
The L15B7 for example have ridiculously small and narrow rod bearings,
yet in stock form can deliver 200+ HP & 200 ft-lb from 1.5L.
Two main kinds of rod bearing loads:
1) Gas loads from combustion, roughly proportional to BMEP or torque, which drops off at higher RPM
2) Inertia loads from reciprocating parts mass, roughly proportional to the SQUARE of RPM.
For auto engines, type 1 loads dominate below 4500-5500 RPM, then type 2 loads grow exponentially.
Lighter pistons & rods help a lot (thus aluminum & titanium), but with modern turbo & controllers,
you can limit the RPM, and just raise boost to increase BMEP and make same or more power.
This permits smaller and lighter components.
docwyte
PowerDork
11/22/22 9:56 a.m.
It's just poor engineering. Rod bearings shouldn't be considered wear items like that. I consider the IMS issue that Porsche M96/7 motors have the same kind of thing, that sort of failure simply shouldn't happen.
te72
HalfDork
11/22/22 10:31 a.m.
Parker with too many Projects said:
Slightly off- topic: Has there ever been an explanation on why this seems to affect the high-output BMW engines more than the Japanese manufacturers, or is it just in how it's reported?
Can't speak for all Japanese engines, but my 1jz had bearings that after ~80k use in all climates, and ran hard after warm up, and raced often, those bearings looked brand new. If I recall they are about an inch in width, but Toyotas are pretty well known for building things on the beefy side.
docwyte said:
It's just poor engineering. Rod bearings shouldn't be considered wear items like that. I consider the IMS issue that Porsche M96/7 motors have the same kind of thing, that sort of failure simply shouldn't happen.
They seem to last longer than K24 timing chains, and those are a bigger pain to replace, yet teh internet loves them some K24 engines.
I'd be willing to replace the rod bearings every two years if it meant 8000rpm every day. Hell I was willing in the put up or shut up sense, but the only E46 M3s I could find that were not stupid expensive were all convertibles. Maybe things have changed since 2017.
Slippery said:
In reply to z31maniac :
On the flip side, you can say that the M20 is overbuilt
I am using an M54B30 crank on my M20 stroker. Need to check the bearing widths on that crank to see if they are the same as the S54.
They are. All those cranks can be used for a stroker M20. M/S50/52, the eta cranks, etc.
I think the largest displacement you can end up making with a longer throw crank and larger pistons is a 3.1 L M20.
David S. Wallens said:
codrus (Forum Supporter) said:
Berck said:
Just... how is it that anyone finds it acceptable that any car built in the last 20 years wears out rod bearings faster than most cars wear out timing belts?
Have you driven one? They're worth it. How many 20-year-old naturally aspirated engines make over 100 hp per liter at the wheels with nothing more than a header, exhaust, and a tune?
Unless it's a plot by Big Rod Bearing, it's just a fact of ownership. On a new car purchase, I can see that fact stinging. Now, we know so going in.
It's $680 in parts for a job (bimmerworld OEM parts kit) that will probably only need to be done once in the time someone owns the car, assuming normal usage. It's a DIYable job, can be done with the engine still in the car using an engine support brace and pulling the oil pan.
Yes it's unusual, but it's hardly the fatal flaw that some people make it out to be.
In reply to codrus (Forum Supporter) :
I was under the impression that the rod bearings only lasted about 60k miles. (Which is also about as long as the rod bearings lasted in G60 Corrados)
...perhaps it is weird to assume that it is normal to drive a funcar 30k miles a year?
Pete. (l33t FS) said:
I was under the impression that the rod bearings only lasted about 60k miles. (Which is also about as long as the rod bearings lasted in G60 Corrados)
My impression is more like 100K? 60K sounds more like a internet scare number to me. Average usage is 15K miles/year, and most people are going to get bored of a car before they do 200K on it.
Mine is a caged race car, so it's on a totally different schedule. :)
The Yamaha 3.0/3.2L V6 in the Taurus SHO was another high RPM screamer that had marginal rod bearings. Basically it came down to when you were doing the 2nd 60K maintenance, it was best to replace the rod bearings. One thing that a lot of folks learned was that 5w-30 was not the right oil for longevity. Most of us switched to a 5w-40 or 10w-40 oil to help those bearings last. More than one engine was saved to see another day after a HPDE event by stopping at a fast oil change place with the owner requesting 20w-50 and then short shifting all the way home.
An interview with Erik Wensberg about the E36-chassis M3–at the time he served as BMW M Brand Manager–might also add some historical perspective:
One small problem: BMW North America simply saw the Euro-spec M3 as too expensive, too complicated for the American market, Wensberg explains. BMW wanted to position the M3 against the Nissan 300ZX, Mazda RX-7 and various pony cars. If sold here in European trim, the M3 would have retailed for about $55,000–about $20,000 too high, Wensberg adds.
There were other expenses to consider, too. The solid lifters would have required regular adjustments, while the M3 was expensive to insure in its home market. “It was simply a car carrying too big of a penalty,” he continues.
Pete. (l33t FS) said:
In reply to codrus (Forum Supporter) :
I was under the impression that the rod bearings only lasted about 60k miles. (Which is also about as long as the rod bearings lasted in G60 Corrados)
...perhaps it is weird to assume that it is normal to drive a funcar 30k miles a year?
That sounds like a lot to drive any car. Even when I had my sport bike, I think it took almost 3 years to put 35k miles on it. And that included lots of 300+ mile days.
codrus (Forum Supporter) said:
How many 20-year-old naturally aspirated engines make over 100 hp per liter at the wheels with nothing more than a header, exhaust, and a tune?
Honda B16a (CRX SiR) in 1988 was right around 100 hp/liter
Honda f20C (S2000) in the 1999 was about 120 hp/liter
Honda b18c5 (Integra type R) in 1997 was about 110hp/liter
All those numbers are with no modifications. Honestly don't know if they are at the crank or wheel though.
te72
HalfDork
11/23/22 10:31 a.m.
In reply to Pete. (l33t FS) :
Something tells me that there is a proper fix to the K24 timing chain issue you describe, but I haven't looked into it. First I'm hearing of it, honestly.
That, and if you lunch a K24, it costs how much to replace? As opposed to whatever BMW engine we're talking about is how many thousands of dollars these days?
In reply to CrustyRedXpress :
All great engines. All four-cylinder engines, too.
I have heard that the length of the S54’s crank doesn’t help things here.
wspohn
SuperDork
11/23/22 11:32 a.m.
S54 bearing life depends on use If you are driving it as a street car and using maybe 6K once in awhile, they are good for 100K plus, but if you do track events with it (quite a few do get used that way) the life shortens and the 60K estimate is probably about when you should start worrying (and testing).
I have an after market exhaust on mine and although I rarely really wind it up, when you do, the sound is glorious. I can see why some owners just can't resist that 7900 rpm level (plus even the stock suspension is good enough to put on a good show on the track, given suitable rubber).
In reply to David S. Wallens :
Agreed!
And I think we can debate all day whether having to replace rod bearings at so many miles is okay or unacceptable.
But as this data from Hagerty shows, rod bearing issues or not, there is demand for these cars. So, I figured, let's get and share some usable info on them.
In reply to David S. Wallens :
I think mine is in better than #4 condition ... yet you bring me $29k and I will put a bow on it and throw in an oil change and two extra set of wheels 
CrustyRedXpress said:
All those numbers are with no modifications. Honestly don't know if they are at the crank or wheel though.
Those are crank numbers, figure 15-20% less at the wheels.
Although looks like some deals are out there as BaT sold a six-speed M3 with less than 100k for $16,250 this summer. Was that an anomaly or the new normal?
David S. Wallens said:
Although looks like some deals are out there as BaT sold a six-speed M3 with less than 100k for $16,250 this summer. Was that an anomaly or the new normal?
That one went cheap even by pre-pandemic standards.
In reply to codrus (Forum Supporter) :
Totally. I was waiting for the gotcha and didn't see one: clean title, no SMG conversion, no big issues.
Sounds like the fact that a dealer sold the car for an individual caused an issue or something?
David S. Wallens said:
Totally. I was waiting for the gotcha and didn't see one: clean title, no SMG conversion, no big issues.
Sounds like the fact that a dealer sold the car for an individual caused an issue or something?
I didn't dig all the way through the comments, but there was nothing obvious to me. I guess sometimes auctions just fall flat like that, and that's what reserves are for?
I paid $15K for mine in 2018, but it had an SMG, the undesirable gray interior, and some cosmetic paint issues. None of those were relevant to the race car build (it was going to get an E36 5-speed no matter what), and I was happy to pay $6-8K less than what a nice 6MT car would have cost.
In reply to codrus (Forum Supporter) :
Guess they can't all be winners.
The lesson here: If you're on the hunt, keep a close eye on all sales because you might get lucky.
Opti
Dork
11/24/22 12:29 a.m.
ddavidv said:
Berck said:
Just... how is it that anyone finds it acceptable that any car built in the last 20 years wears out rod bearings faster than most cars wear out timing belts?
What he said.
Defenders of the Sacred Roundel seem to accept this as part of life but to me it's simply piss poor design. Couple this to all of the other things that fail on the E46 platform and you can keep 'em for yourself.
Although I never cared enough about the E46 M3 to consider one given the problems, the E90 M3 always tickled my pickle, and I did do quite a bit of research on owning one over the last few years.
BEBearings seems to think the S65 bearing problem stems from too tight clearances, and large manufacturing tolerances. They have a page dedicated to it, and even though its incredibly dry, it was a very interesting read.
IIRC their findings led the OE supplier Clevite to write a paper on it. It was something like Nominal rod bearing clearance for an S65 was around .001 maybe .00125. Which is about half what a decent clearance would be in a performance motor. Add into the equation stacking from the large tolerance of the other parts and with everything in spec the actual rod bearing clearance could range from half the nominal clearance (probably a quarter of what would be considered decent) .0006 (explaining the super early less than 10K mile failures) to over .0021 (much closer to what youd want explaining the higher mileage cars not having bearing issues.) Also they speced a super thick oil which is terrible for super tight clearance, and you cant run a thin oil because those are terrible for high revving performance engines.
Take their findings with a grain of salt because they are trying to sell you bearings, but I think the info seemed pretty solid when I read it. Regardless Im firmly in the "design flaw" camp, which is said because I love the cars, but I just cant wrap my head around rod bearing being a maintenance item on an incredibly expensive to repair or replace engine.
In reply to Opti :
FWIW, I went into this knowing rod bearings were likely in the car's future. Part of these projects, though, is to learn more so we can then discuss it.
More updates on the M3 to come as a box from BimmerWorld just arrived.
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