As the owner's manual instructs us to not rev the engine (past 3k?) while lifter noise is present, I have to believe some noise is to be expected. Constant or excessive lifter noise is another matter and well documented in this forum. Searching the forum will likely bring up several entries.

Memphis area temps are in the mid-low 30's F (or near 0C) and with 10W30 synthetic I'm not having this problem. My car does rev as yours does on cold start.

Who changed your oil? What was used? What brand filter? Whether it really matters or not, the Volvo and Mann filters have an "anti-drainback" valve that supposedly keeps oil from draining back through the filter when the engine is off. I don't know anything about oil control past the lifters so I can't comment. I just use Mann filters as they're supposedly identical to Volvo.

Shortly after buying my car one lifter started clacking away and was cured by flushing the oil with a randomly selected DIY product from the local parts store and swiching to the proper weight synthetic. I haven't had the problem since.

How many miles on your car? If it's more than one lifter and the oil is of proper weight I'd suspect you're likely pulling air through an 0-ring in the pan. Not uncommmon, and the second step in troubleshooting constant lifter noise after a flush, and proper filter and weight oil.

Good luck,

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Erwin in Memphis, '95 855t