I'm not sure if the crank hub gear in the current M3 engine, S55, is as big a problem as the forums make it out to be. Seems like modified and stock engines suffered from the crank hub problems and needed to be replaced.

 

I guess I'm not keeping up with BMW issues as well as I thought... although I think the rod bearing issues are oil weight/warmup related...

 

The E46 M3 had the occasional motor that would kick a rod. It was also an earl 2000's motor making 100hp/L naturally aspirated and revved to like 8500 IIRC. The ones that got driven hard occasionally broke.

The E90-92 V8 rod bearing issue was a tolerance stack up problem. I think the internet also made that seem like a larger issue than it is. VANOS issues are more a thing for the older cars (E46 and older). Don't here about it so much in the new stuff.

There is nothing wrong with nikasil liners other than it's not repairable. You either have to entirely redo the coating, or hone it off and use different rings for the now iron cylinder.

 

i've got an e92 - no issues so far, but i plan to do the rod bearings. aside from the rod bearings & the throttle body actuators, i dont see any issues with these motors. been running RL 5w50 in the car, which is thicker than most 50s, but not as thick as castrol's. bimmerworld races their e9x on RL 5w50 with no issues. once the rod bearings are upgraded, there are no longer any issues with it.

i think the e46s have subframe issues and the e9x's may also, but much less of an extent than the e46s. i love my m3 lol.

 

My father in law's e36 M3 has never ending cooling problems. It's always leaking. It seems as soon as I visit and fix one leak it springs another. I dunno whats up with German's and their cooling systems but this is a perfect example of over engineering a problem.

 

I don't think the issues a mid 90's car has applies to a 2019 vehicle.

 

I was more just speaking to how Germans have historically had a hard time with cooling systems. I also thought we had reached the part of the thread life cycle where we where *****ing about what ever random stuff as loosely related to the OT as possible. I guess I jumped the gun

 

Just to clear up what I meant, I don't mean that the thick oil is to blame, it's that people don't warm them up properly, and the thick oil makes the engine more sensitive to things like that...

 

The E46 M3 motor had a high-profile service action on the rod bearings for wearing out. They fixed it in the later cars, but improperly clearanced rod bearings took out a lot of early motors (10% failure rate). Even revised bearings still aren't a permanent solution.

For E90/92 M3s and E60 M5s, same clearance issue, including stacking (as mentioned). BMW tried to cheat with a bearing clearance good for power and economy, but bad for longevity on normal oils, never mind 10W60. The rod bearing clearance was 0.001" too tight from the factory and they ate bearings, potentially leading to a catastrophic failure. They didn't learn the lesson from the E46 bearing issue, which was a big oversight.
http://www.bebearings.com/Overview.html

The Nikasil liners were definitely a problem beyond being unable to be repaired - they actively wore out with some fuels, which had obvious consequences: https://www.torquecars.com/bmw/nikasil-issue.php

The 135i and 335i, in addition to the HPFP issue, also had wastegate actuator issues as well. The backyard fix may be simple, but it led to a lot of turbos being replaced.

 

yea it's some of that, but as mentioned below it's that the clearance was too tight for the oil used, plus not warming up, etc. my m3's got around 28k with no issues, but the bearing upgrade does permanently fix it on the s65s. anyway...

 

well d@mn.. I was wrong... BMW engines have tons of issues...

 

I wanted to track an E46 m3. Good price on smg models. Should I be worried w bearing failure?

 

I don't know how the SMG will handle heat of road racing, so look into that. Also copied this from another site:



Hey everyone. Of course you know there are some big maintenance items for the E46 like the subframe reinforcement, rod bearing, and VANOS but there are a few others as well.

I wanted to put together a list of issues here so it's kind of a one-stop for all things maintenance. I've done pretty much all of these services and wanted to share to the new owners and prospective owners what to expect maintenance wise. So here we go.

Full article here: Ultimate E46 M3 Maintenance Guide & Schedule

1. Rod Bearing - Excess heat and friction will cause your S54 rod bearings to wear overtime and at about 100k miles you should really look into replacing your rod bearings. There are some additives you can add to limit the wear, but it’s only short term. We did a full write up on treating your engine with Liqui Moly MoS2 with oil sample tests in case you’re curious. In the long run, you want to replace. BMW did create a service action recall to fix this premature issue, but still only short term.
2. VANOS - There are multiple issues associated with the S54 VANOS unit. VANOS solenoid solder connection disconnects, cam bolts become lose and snap inside the engine, worn down oil pump disc, VANOS hub tabs break and gets tossed into the engine, VANOS piston seal o-ring deteriorates, and chain guide wears down. If you’re having timing issues or hear abnormal ticking coming from the solenoid, you definitely want to consider doing a VANOS overhaul. Some get lucky, but when the metal hub tab breaks off it’ll most likely go into your engine causing major damage.
3. VANOS high pressure oil line - The S54 VANOS oil line creates up to 1,200 psi in the feed line and the neck area closest to the banjo bolt on the solenoid tends to crack or burst. The VANOS high pressure oil is used to maintain responsive and accurate camshaft adjustments. Failure in this line can do serious damage to your engine.
4. Subframe reinforcement - The rear mounting points for the subframe can rip out in the sheet metal caused by excessive torsion load from the differential to the chassis. We’ve literally seen a chassis split in half!
5. CPV - The CPV has an o-ring that tends to flatten and harden over time because of excessive heat which causes a leak in the line. The valve is located behind the exhaust manifolds which makes it a must-replace job if you’re taking out the headers for whatever reason.
6. Radiator - The OEM radiator has plastic end tanks which are prone to crack caused by high-low temperatures. Coolant temperatures can reach up to 207 degrees under normal operating conditions and quite possibly higher during track days. Plastic expands in heat and contracts in cooler conditions so it’s just a matter of time until your OEM end tanks leak!
7. Radiator hose - The OEM coolant/radiator hose gets brittle and cracks overtime leading to leaks. Just like the radiator issue above, hot-cold temperatures will prematurely wear out the OEM material. If you’re upgrading your radiator to all aluminum, you might as well spend the extra $80 to upgrade your hose kit.
8. Differential bolts - Excessive torsion load may cause stock differential bolts to snap. Even when you accelerate and decelerate, the drivetrain load causes force and adds stress on the differential bolts. Now, go out to the track where you put the car in a more severe environment, you might want to really consider replacing bolts. $12 for a pair is worth it.
9. Rear shock mounts (RSM) - There have been many reports on M3Forum on the rear shock mounts blowing out of the washer and causing a bit of damage to the shocks. If you hear squeaking, rattling, or clunking it may be a sign that the RSM is going bad. Monitor around 60,000 miles.
10. Rear trail arm bushings (RTAB) - Premature wear of OEM bushing can result in poor handling, excessive tire wear, and alignment issues. In some cases, members on M3Forum have reported premature bushing wear at ~40,000 miles of daily driving.
11. Front shock tower reinforcement plate - When using aftermarket camber plates, the front strut tower may began to deform or crack when driving in “poor road conditions” due to uneven distribution of pressure.
12. Rear spring perch reinforcement plate - The aluminum cast construction of the lower arm, only on the E46, may cause the spring perch to deform or crack. Similar to the strut tower reinforcement, the uneven load from an aftermarket spring perch may cause improper seating thus damaging the suspension. This applies if you have after market height adjusters.

Shoutout to Obioban for the information he put together in his thread that guided my servicing.

 

Oh. Wow. Makes you wonder why anyone would buy one

 

Or how about that prices are going up?