correct operating temp for a 2001 lesabre?... and coolant leak

I just replaced the thermostat in my lesabre and the heater is now working much better. The digital temp gauge now reads around 200 in city trips of a few miles. At autozone I had the option of buying a 195 degree thermostat and a 180. I went with the 195 since that's what the manual says to use. In Autozone's database, the 180 was listed as an "alternative temperature." :confused:

Is a temp around 200 OK? Should I have gone with the 180? My car has about 75k on it and doesn't threaten overheating...

Also, there was and still is a very slow coolant leak around the seal of the
thermostat housing. The old and new O-rings are seated just fine, and the old one did not appear damaged. I torqued down the bolts well. Don't know why it would leak like this. Is this unusual? Should I throw a little RTV in there?

195 to 200 is ideal.

Along with what maxwedge said, the temperature you described sounds just fine. About your thermostat housing with the leak, what kind of sealant did you use? Use the RTV used for waterpumps, the stuff I have always used is blue in color and so far has always been leak-free. I found it in Auto Zone. Good luck!

There wasn't any sealant on there at all actually, just a rubber O-ring with a groove in it that fit around the edge of the thermostat. I have a bunch of grey and some black RTV. I think the black stuff is for high temps. Either way, the temps right there don't get too insane, so I'll throw one of those on there...

There wasn't any sealant on there at all actually, just a rubber O-ring with a groove in it that fit around the edge of the thermostat. I have a bunch of grey and some black RTV. I think the black stuff is for high temps. Either way, the temps right there don't get too insane, so I'll throw one of those on there...
It shouldn't need any sealer. Maybe it just needs a new rubber gasket. They're available from the dealer or from parts houses. Check around the rubber to be sure it's well cleaned before putting in the new one.