Dye plus snake light. Tricky part is getting UV source in with the snake. I recently acquired a 1900 lumen flashlight and poked it in the gap next to the oil filter and for the first time could see wet oil. Normal light couldn't get down in there.

I think with the snake it will be very obvious.

Also; you will want to remove the stiffening plate to clean the engine after anyhow.

A low profile ratchet with 16mm works perfectly to hold the nut for removal and I put mine back on but side down.

You can reuse 3-4x following the torque to yield steps, or you can do like me and get some 12.9 bolts and locking washers (nord lock), so you can reuse indefinitely.

Don't forget to put the back four bolts in if you need to drive before putting the stiffening plate back on! They hold the anti sway bar. It's a really noisy (yet humorous) ride if that sucker isn't pinned down.

I will be changing my control arms today and plan to remove the plate until I get the OFHG replaced.

I had the plate off for about a year on wife's car; you lose some torsion stability; the car will wiggle like a convertible with the top down, and you are at risk of "frame" damage if you have a front end impact as it's a main point of keeping the car rectangular, probably takes about 50-60,000# of force to parallelogram eg 10g of crash force.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)