I run the 2" Marlin spacers on each corner.
My personal way of doing it was this...........
Use RED locktite.
I didnt torgue anything.
I used a 4 way and tightened the studs to the axles till it didnt budge anymore
then I tightened the wheels to the spacers in the same fashion.
I have checked em twice and could only budge a couple of the nuts out of all of them but just barely at that.
I think your biggest factor is if you are running aluminum wheels on the Marlin aluminum spacers, aluminum is soft and will settle a bit more.
My wheels are steel so mayber that is why I have had no problems.
Red loctite is supposedly permanent and heat is needed to remove it. What about taking the spacers/hub back off if I bust a birf on the trail?
