Clunk when starting

[twinmill28]

Been meaning to post my "start-up clunk" for awhile to see if anyone else's duece does it. I'm not so concerned with mine as it's been doing it for awhile and randomly (more than a year) and everything is good.
Mine is just at startup when it's cold, just after the key springs back from starting, right as the engine has started. I'd been thinking it felt very similar to engaging the transfer case, but not as pronounced or loud. You can feel it more than hear it (but can still hear it). It feels like it's going into gear with the trans or something on those lines. Once the engine is actually running, it is all smooth and all is good.

I'm so tired of sorting out car noises and peculiarities that it usually takes a catastrophic failure for me to worry too much any more--one of our last cars was a Ford and it did all kinds of stupid things that the dealers kept laying on "normal operating condition", right up to the tranny taking a dump at 64K miles, and the engine throwing a rod shortly after 84K miles.