The support tube on the M60 was originally a simple steel tube. BMW later updated the filters requiring installation of a sleeve with a check valve over the steel tube to prevent oil draining back into the engine at shut off. The sleeve is available separately the metal tube only comes with the oil filter housing. If the filter is stuck in the cap- then chances are it has the plastic sleeve stuck in the cap with it. You SHOULD be able to pop the cap off of the filter by twisting and pressing it sideways. If you see the sleeve sticking out of the bottom of the filter- you can pry on the sleeve using the filter as leverage. If this doesn't work- then I would replace the adapter sleeve and the filter cap. The sleeve is BMW part number 11-42-1-745-392 the housing cap is part number 11-42-1-736-674.
Hopefully this helps you out!! --Cliff
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