Have you had to add Coolant yet?
 

My coolant light came on today and I added about 20 oz to bring it up to the full mark. I have about 12,000 miles on the car. No noticable drips.

Anyone else had to add any, and if so how many miles??

What coolant is recommended?? I believe that you have to add non-diluted coolant (no water mixture) as the water will corode in the jackets. Does that seem right???

You would use a mixture of distilled water and coolant just like any other car. The mixture depends on the temperature you want to protect the system down to. Usually 50/50 is a good mix for most areas.

This is from the shop manual:

I used about 50/50 mixture with the right kind as spec'd in the manual. I bet is is just from the fact that the engine caompartment is hot that it evaporates some. I have had the car 15 months.

My overflow tank is still where it should be and radiator is still full at 11,275 miles..

Just wondering though, but if some vehicle's lose that much coolant due to heat, then that means you should not just refill it but do a drain and flush since the old stuff is now too concentrated. that makes sense

If I were you I would have the car checked out by a service dept. Twenty ounces is a 6% loss of coolant, which would cause me concern. I doubt that evaporation would account for that much loss and if there is definately no external leak, I would be concerned that the coolant might be leaking internally into a combustion chamber or into the oil. Don't mean to alarm you, but ya gotta look at the worst case possibilities.

If there is no external leak, I wonder how to tell if it is leaking into the engine or combustion chamber. Maybe the oil could be sent off for analysis? My oil doesn't appear any different than normal going into about 2k miles since last change.

My dealer offered to put it up on the rack for a check, sounds like I ought to do that first.

Yeah, it would be smart to at least take it in to "register" this issue in case something comes up in the future where you need to demonstrate when this was first noticed. Make sure they check it with the engine fully warmed up and running so that the cooling system is pressurized and all the components are expanded to where they would be when driving.

Oil analysis might also be a good idea if they don't find a leak. Let us know what they find.

As others have suggested, take it in to the dealer.

I've got 16k miles and the coolant level has remained the same as day 1. When I first got the car, it was hard to see the coolant due to the level it was at - just below the seam on the reservoir - so I added some Red Line WaterWetter.

FWIW, I did not observe any differences in the temperature guage after adding the Red Line WaterWetter.

yeah, dealer refilled it at about 10k miles. no light came on, it was in the middle of min-max signs...

I've got about 25K miles on mine, and have added coolant three time. Twice at the first real cold snap of each winter which would set the light, and once after an eight hour straight highway drive. I think that it just evaporates off some when the engine operates at higher temps. I haven't found it to be too much of a problem, and have found no leaks, and I have looked all around the engine. I consider it normal.

1 year and 6000 miles; still at full.

Do a coolant pressure test. It's the only way to be sure.