M276.9 3.5NA engine oil cooler removal, is NOT as easy as M272
How would you recommend that I fix this? Remove the bolt from underneath and get a shorter bolt ?
I assume that the bolt from underneath shares the same female threads.




.If female thread is not rusty, it may be easy to spin it out .......of course with special tools for this kind of "rescue" work.
It looks too clean of break to be sheared off. Check out the thread marks on the engine mount.
Leads me to believe that someone put a load on the engine mount from underneath with the rear bolt installed.
This could explain the shearing. But that is a M8 bolt. Does not seem likely to occur
I was just wondering if was from an extra long bolt from the under side.
Last edited by mercerized; Jun 17, 2025 at 01:04 PM.
HEX replacement is complete.
The broken stud is in work. started drilling for the extractor. I am not confident about removal as it seemed really stuck.
Last edited by mercerized; Jun 23, 2025 at 01:25 PM.
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Here is a 4matic subframe, no broken engine mount bolt
I think at one point in time the engine mount so worn out, it shake like crazy and broke the bolt.
Previous owner reported at 36k miles running over a truck axle from an accident ahead. Had to replace control arm, half shaft, one wheel, and the plastic covers. Very likely that caused the bolt to shear and nobody could see that.


