Do a google search on this newsgroup, and you'll find plenty of
discussion on it (BTW - I own a '99 Concorde with the same engine that
now has 125k+ miles on it, and it is running great - no problems).

I think the following will alleviate some of your fears about your
particular engine: I think *without exception*, every post I have seen
here or on www.dodgeintrepid.net forums about a 2.7L sludge failure has
been in the window of 55 to 85k miles.  This could be due to one or a
combination of :
(1) Mostly hiway use (i.e., very little short-trip sludge-producing driving)
(2) Good mainenance (routine oil changes at closer to 3000 mile rather
than 10,000 mile intervals.
(3) Luck of the draw on getting good engine (I think this is the least
likely of the three since the root cause IMO is marignal lube system
design issues).

Since I drive my Concorde 80 miles a day and do the oil changes, I think
that is why it is doing so well.  I've seen inidications that it was a
sales fleet vehicle in its previous life, so it probably had hiway miles
and decent maintenance then too.

When I bought mine used at 58k, shortly thereafter, when I found out
about the tendency of the engine to sludge up and fail, my solution was
to use 1/4 qt. of Marvel Mystery Oil in the crankcase with every oil
change, target the oil changes for 3000 miles (in reality it probably
has worked out to 3500 miles average), and change the filter with every
change using a good filter (I use Purolator Pure One™, but there are
many other good ones out there).

If you had fewer miles, I would say to switch over to synthetic, but
that would probably be a mistake on your engine *ESPECIALLY* since the
primary concern is sludge accumulation.  Synth. will break the sludge
down fairly quickly and could very likely block the small oil return
galleys and valve lifter (AKA lash adjusters)ports and bring about the
exact failure mechanism you are trying to avoid.  Using the MMO plus oil
& filter changes like I suggest will do a more controlled, gradual
cleanout.  You *could* do a similar thing with synthetic (transitioning
over to it by increasing the proportion of synth to non synth, say 1 qt.
synth to 4 qts. non-synth, then 2 qts. synth to 3 qts. non synth., etc.
until you were at 100%), but that is a personal choice, and there is a
risk no matter what you do (some would say let sleeping dogs lie and
continue with regular oil with changes at 3k miles).

It is common advice in the Intrepid community to switch over to either
the 3.2 or 3.5 engine (I forget which) if you do experience a failure of
the 2.7L.  IIRC, it would also involve swapping out the PCM.  Again, do
a google search on this newsgroup - it has been discussed before, with a
link to a site for doing the swap (also do a search within
www.dodgeintrepid.net - they have an excellent search engine, and
there's guys there that are intimately familiar with this - one guy
there makes a living rebuilding 2.7's).

Bottom line: I think you're safe since your engine has made it this far.

Be aware that that engine has a timing chain (good), but that it is an
interference engine (not so good), with the implication that if the
chain ever breakes or slips, you could have valve damage.  The good news
is that, except for the 55-85k mile sludge-related total failures, in
which case all bets are off, I have never read of the timing chain
letting loose on this engine (i.e., apparently it is good for a couple
of hundred thousand miles).

HTH!

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')

If it's gone this far without failing, it has probably been properly
maintained, as in reasonably frequent oil changes.  I'd just make sure
to change the oil at least every 4K miles or so to prevent the sludge
problem.  If you do a lot of short trips, more frequent oil changes
would be good.  Hopefully you engine will keep going for a long time,
but if it does fail, it might be worth replacing it with a 3.2 or 3.5,
though to do so would require swapping the ECM and would, it other ways,
be more complicated than staying with the 2.7.  Good luck.