As pictured above you certainly can do timing cover gaskets without removing the valve covers. We typically recommend doing valve cover gaskets and timing cover gaskets at the same time whenever we are working on an N62 equipped vehicle. There is always a possibility of the valve cover gasket leaking when the front timing cover is disturbed. It is much more common on a vehicle that has original or old valve cover gaskets. If the valve cover gaskets have been replaced recently then they are much less likely to leak and far easier to reassemble.

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2004 BMW X5 4.4i-Sports Package-Premium-140,000 Miles