E93 Underbody Chassis Brace Bolts & Torque Spec

[Zap]

I'm finishing up an ///M Performance Exhaust install on my E93 M3 and have run into two issues.

I may have had a defective bolt or torqued it too hard on the Chassis Brace - thankfully I am very lucky and the head snapped off, but the bolt still rotates, so I'll be able to remove it.

Can anyone tell me the torque spec for the 13 mm bolts that attach the two sets of brace bars - as well as how to find the part number to replace one or both bolts? I tried looking on RealOEM and can't find that section of the car for the breakdown. It is an Grade 8.8 with a washer.

Secondly, I now have a brand new exhaust that has defective tips due to BMW allowing the factory to have a drunken holiday as seen in this posting, and have to figure out where to address that issue which should be covered by the part warranty.....

https://www.m3post.com/forums/showthread.php?t=1763089

[Zap]

I found the body brace diagram in another posting:

Vehicle Trim was the category > Reinforcement, body

51618045950 is the main piece. I'm looking for the bolt that goes into the middle bracket on piece #4. Not sure why that isn't visible in the drawing, or if it is the same as #4 where it connects on the end.

[Zap]

The dealer has an inquiry open to Germany about this... in the meantime I'm still searching as the car has been sitting.

[roastbeef]

torque spec on that one is snug-af.

[tbuck]

The bolts are shown in the diagram on the right and the specs for the bolts are found in the list at the bottom. The bolt may be broken but you can measure it to see what size it is. You need to know the diameter (M8-M10, etc) and the length of the bolt from the head to tip (20mm, 30mm, etc) then you will know which one to order. For example from above is M10x25. And honestly you do not have to get the bolt from the dealer as Home Depot has an excellent selection of metric bolts in many grades and finishes. I have on numerous occasions gotten missing bolts there rather than wait days/weeks for the dealer.

[Zap]

I have been meaning to post - I eventually sorted out the situation and identified the bolt myself.

It is M8x22 Grade 8.8 with integrated washer. BMW Part 07 11 9 905 739. The replacements were $1 or so apiece and they got them the next day. I figured that I should just replace both to be on the safe side, and haven't had any issue since.

My car was inspected by the service department for the exhaust parts warranty in the meantime, too - so now I wait to hear back about the case that was opened.

[Throatpunch]

The same bolt on my spins with the head still on. So far this is the second issue after work was done by one of the sponsors here on my car 🤬

[Move Over]

All of the 13mm bolts for the exhaust brace, trans mount brace and center carrier bearing are 15ft lb. or approximately 1.75 ugga dugga on my Milwaukee impact.