Everytime I go to loosen the oil cap, the extension neck comes off with it. I've already tried replacing the o-rings on both the neck and the cap, but the issue still persists. I just wanted to know if this happens on everyone'* car, or just mine. :o

it happens to mine aswell sometimes, if i am conscious of it, i will almost always only remove the cap, but once in a while they stick. I think it is because the oil splashes up on the lower seal and not the upper seal and lubricates the neck/valvecover seal and not the neck/oil cap seal

That makes perfect sense. Thanks Toasty.

Yep. Mine does it too. I just grab the bottom tube with left finger and thumb and turn the cap off with my right hand. Easy enough.