DIY Reference - Common E9X M3 Torque Specs

[eriqm]

thanks for the post awesome input. no more guess work. Again, thank you.

[k2em1]

Anyone knows the torque spec for the flywheel to crankshaft bolts for #21212283820? I found this indicating an M62 bolt that requires 105Nm (77.4 Lb FT) but not quite sure.

[Theodore]

Originally Posted by k2em1

Anyone knows the torque spec for the flywheel to crankshaft bolts for #21212283820? I found this indicating an M62 bolt that requires 105Nm (77.4 Lb FT) but not quite sure.

That's correct the BMW TIS says the torque is 11 22 1AZ which in your link is 105NM. Note the text with the spec says the screw threads must be oiled when achieving this torque, something you don't see too often on this car. Added to thread.

[k2em1]

Originally Posted by Theodore

That's correct the BMW TIS says the torque is 11 22 1AZ which in your link is 105NM. Note the text with the spec says the screw threads must be oiled when achieving this torque, something you don't see too often on this car. Added to thread.

Thanks for the awesome thread and tip!

Can you also help with the numbers for clutch bolts and other stuff needed for clutch work? Part number is 21212284034.

[mboob]

Thanks for this write up, it's very helpful!

[E90Freedom]

Thanks, super helpful!

[Scharbag]

I think there is an error as the first post says to tighten the oil sensor unit to 18Nm. That is way too tight according to ISTA.

Cheers,

[Theodore]

Good catch, correction made.

[JoeFujiwara]

are you able to get torque specs and sequence for the s65 motor, like the bedplate and so on? that would help me a ton i would really appreciate it

[TrueToBMW]

Anyone know the toque values for the rear sway bar end links (stabilizer)?

Figured they might be the same as the front, but wouldn't hurt to ask, thanks.

[DrewM]

Amazing post thanks for the effort, easy bookmark

[$alty$krt]

This is not the fuckin right spec for engine mounts my shit broke thanks a lot fuckin asshole next time share the right shit

[IamFODI]

Originally Posted by $alty$krt

This is not the fuckin right spec for engine mounts my shit broke thanks a lot [bleep bleep] next time share the right shit

1. Welcome to the forum!

2. Yes, it is the right spec.

3. Your profile says 2011 328i. This is an M3 forum. These specs are for an M3, which apparently has bigger fasteners and calls for 2x the torque. You didn't use the M3 spec on a 328i, did you?

4. Even if you did... 56 Nm is not a ton of torque. You sure that's all you used?

5. Blaming others for your mistakes is bad for you.

6. Melting down on a free resource that obviously took a lot of time to assemble, and that a lot of people are grateful for, isn't a great way to introduce yourself to the community.

[kiquos]

One Torque setting I did not see and need are the bolt to the Diff side flanges. and rear cover
E92M3 DCT Rear Diff
See pic. thanks

[Theodore]

Originally Posted by kiquos

One Torque setting I did not see and need are the bolt to the Diff side flanges. and rear cover
E92M3 DCT Rear Diff
See pic. thanks

21.7 NM (16 ft lbs) and BMW says to "Tighten down screws in crosswise sequence"

Edit: Added to the reference page, thanks.

[kiquos]

Originally Posted by Theodore

21.7 NM (16 ft lbs) and BMW says to "Tighten down screws in crosswise sequence"

Edit: Added to the reference page, thanks.

Thanks.. This is for the side shaft cover bolts? (seems VERY low) or is this for the rear AL cover? thanks

[Theodore]

Originally Posted by kiquos

Thanks.. This is for the side shaft cover bolts? (seems VERY low) or is this for the rear AL cover? thanks

Yes, the reason is they are M8 screws and only grade 8.8 so they can't handle that much torque.

I added the rear differential cover screws to the reference page which have a 60NM (42 ft lb) torque spec with Loctite 270 (green thread locker), but they are larger M10 screws and have greater tensile strength as they are a grade 10.9 screw.

[B8bydesign]

Originally Posted by Mike6699

Hi guys,

I searched and couldn't find any info, but can anyone tell me what the torque specs are for the belt tensioners? Specifically bolts 1 and 2 in the pic.



Thanks!

https://www.m3post.com/forums/showthread.php?p=29889471

Can anyone confirm the torque specs for bolts 1 and 2 in the diagram above for the tensioner assembly? There seems to be a few different numbers floating around in the original thread and online for those 8.8/10.9 M8 bolts and just looking to confirm.

[drwankel]

Mods, can we sticky this thread please?

[spammysammich]

This definitely should get pinned to the top

[BenFenner]

Another great thread from Theodore that I'm just finding/needing now!

Originally Posted by k2em1

Can you also help with the numbers for clutch bolts and other stuff needed for clutch work? Part number is 21212284034.

I would also like this information. The bolt itself is part number 21207548052. There are 6 of them that mount the pressure plate/clutch assembly (21212284034) to the flywheel.

Also, does anyone have a part number for the flywheel-to-crankshaft bolts? I can't find them on RealOEM nor can I find the part number mentioned anywhere on the forum from my searches. I'm also curious if they are one-time-use/torque-to-yield? I guess that's more important for me to know...

Edit: I'm told the flywheel bolts don't have a part number and can't be purchased (easily) on their own. The bolts do not seem to come with the flywheel when purchased either (yes they do, see edit below). I hear people buy the flywheel bolts for an S55 engine if they need, since they seem to be the same. I'm also told they are not one-time-use, so that's good...

Edit 2: The flywheel bolts may not be torque-to-yield (TTY) bolts, but they certainly are one-time use. Let me explain. The bolts are captured in the flywheel. Unless you start drilling/cutting/grinding away at the flywheel, those bolts are not coming out. And then as you can imagine, my new flywheel did come with new bolts already captured in the unit. At first I didn't think it came with any bolts with a quick look, since they were not loose in the box. But once I removed my old unit I realized where they would be and sure enough the new LUK flywheel had new bolts/hardware in there.

I highly doubt the S55 flywheel bolts mentioned above would have small enough heads to be used with a stock/OEM/LUK flywheel unless you drilled out the access holes to a larger diameter. So they may work for aftermarket/light-weight units but not the stock stuff.

[BenFenner]

Originally Posted by BenFenner

I would also like this information. The bolt itself is part number 21207548052. There are 6 of them that mount the pressure plate/clutch assembly (21212284034) to the flywheel.

Two different people have told me the pressure-plate-to-flywheel bolts have a (assumed dry) torque spec of 34 Nm (25 ft-lbs). One of them also said to not reuse the old bolts, but I'm still not really sure new are necessary. I'm still researching, but if anyone has the TIS info or other definitive source I'd love to hear it.

Edit: The same person saying not to reuse the bolts is saying new ones come with thread locker on them (which makes sense and seems to be confirmed via parts store pics online) and to at least apply blue Loctitie if you're going to reuse the old ones. Which certainly makes sense to me...

Edit 2: I got real TIS info and it calls for new hardware. I'm not sure why, but there it is and it is "definitive". Certainly people re-use this hardware, but that is not advised by BMW at least.
If I had to guess, I'd say the bolts are not torque-to-yield but BMW wants new ones each time because the factory units have a dry thread locker compound applied that BMW wants to make sure is there. Of course we can add back our own wet thread locking compound (medium/blue seems appropriate) but presumably that will change the torque spec and BMW doesn't want to have to contend with that so they just say "replace ze bolts!".

The torque spec is where things get tricky. According to the first screenshot below, it looks like the S65 almost assuredly uses M8 10.9 ZNS-coated hardware (RealOEM supports this as well), and TIS calls for a jointing torque of 15 Nm then a final torque of 25 degrees.

But then the second screenshot shows M8 10.9 ZNS-coated hardware calling for a jointing torque of 15 Nm then a completely different final torque of 90 degrees.

Crazy, huh?

This might be why people just use the non-ZNS-coated spec of 34 Nm (25 ft-lbs) and call it a day...