I just replaced my wheel! Indeed that allen bolt was tight! Could not budge it with a regular allen wrench and a cresent wrench. I bought a 3/8 drive 10mm allen socket and used my air impact tool. I just slowly pulled the trigger and a couple of wacks of the air tool and it came right out! Was a piece of cake and yes I think there is locktite on threads. Be safe if airbag equipped and disconnect the battery cable!!!!

Smokie

__________________
95 E420 BigBlue
500E Sway bars
2001 C Class 16 in. Rims
KYB Struts and shocks
Rear spoiler
American Stitches Wheel
Bigred 99 F250 Powerstroke
JVC EXAD Mp3 player
JVC EXAD GPS