Just finished changing the rod bearings in my '09 M3 with the WPC coated bearing set and ARP rod bolts. Did it preventatively. Car had no noise or signs of bad bearings, just gets tracked a lot and is S/C'd. Blackstone reports always came back raving about the high quality of the samples sent in. I have been seeing enough horror stories lately that I decided since I plan on keeping the car for awhile I should just bite the bullet and do it. 15hrs total from first to last bolt and test driving.
I want to share some insight and wisdom to tearing in to it yourself. Just a crude write up as a basic guide of what has to happen and things I wish I knew before starting.
Some info on the car: '09 E92 M3. 61k ESS SC since ~20k. Tracked fairly often. Used in the One Lap of America this year and will be next year. Always changed the oil with Liqui-Moly GT1 10w60 and Mahle filters. Every 5k or three track weekends. Also took the car on a 12k road trip around the country this year. Never beat on when cold and warmed up before hitting the track.
To be fair, I am a technician by trade and own a shop with a few lifts, and I don't think I would tackle this one on the ground with jackstands. Laying on your back getting dripped on for an hour while you swapped the bearings wouldn't be very fun at all. Also getting the subframe down and clear would be a PITA without being able to lift the car off of it and slide it out of the way.
Started by disconnecting battery, pulling all undertray shields, draining all fluids, and tearing everything down up top.
I removed the intake plenum, supercharger & mounting bracket, ignition coils, plugs, coolant hoses on the front of the engine, radiator fan, radiator (just to make more room, not absolutely necessary), both belts, oil cooler lines, AC belt tensioner, AC belt idler pulley, disconnect power steering lines at plastic cooler connectors, and power steering reservoir & pump as an assembly left attached to rack and subframe. Support the engine with a transverse engine hoist
Removed strut upper mount bolts with plans to drop the subframe out as a complete assembly with struts still attached. Worked pretty well.
From underneath I removed the oil cooler line connections from oil cooler, ABS sensor wires, xenon level sensor connector, calipers from hubs, both engine mount to subframe bolts, and the steering shaft to rack bolt.
From there I lowered the subframe on to four jackstands, removed the subframe bolts, removed the strut mount nuts, and lifted the car off of the subframe.
Removing the oil pan is a lot of T30 torx of various lengths. You will need a T-handle or long necked T30 as about 10 of the bolts are recessed in holes only about 7mm wide but about 4 inches deep. There are also four bell housing E12 external torques that need to come out. The lower AC belt tensioner bracket comes off too.
Once the pan is down there are around 6 bolts in total needed to remove the pump pickup tubes and get to the rod caps
Changed the bearings one at a time starting at one and making my way back to eight as I rotated the engine. The rods came right off the crank and tapping the upper bearings around lightly and removing them was pretty easy. New bearings are marked blue and red. Blue on top, red on bottom. Make sure to line up the rod caps with the correct orientation of the bearing notch as they are cracked rods and the caps only fit one way. The ARP rod bolts come with lube and Bimmerworld spec'd them at 40ftlbs. Would have been nice to have a stretch gauge but torque works fine.
New oil pan gasket and time to put the subframe back up. Easiest way was bolting the strut mounts up in to the car and allowing the subframe to hang by the struts while I lined everything up and used pole jacks to support it as I needed.
The rest was reverse of removal. Order of operations really matters when putting the front of the engine back together. The p/s pump has to go on first and the alternator belt can't slip up above the water pump pulley with the idler for the AC belt installed. Also oil cooler lines have to go on after the AC belt is reattached.
Things I wish I knew or would have done while I was in there:
New seals for the oil pump pickup tubes and the oil cooler lines would have been nice. Also it was a perfect opportunity to upgrade the lower engine mounts. Good time to change your idler pulleys and belts while you have it all torn down. Plugs were done not too long ago so skipped it, but thinking maybe it would have been worth it to throw a set of coils in. Easy enough to do later.
Good luck if you decide to go at it. My upper bearings showed wear on all cylinders. I view it as necessary preventative maintenance if you're planning on keeping the car for awhile.
