I have a 2001 explorer v8 with auto. transmission. On cold mornings before the car has even been started, I can see a spot on carport where antifreeze has leaked out. On warmer days, nothing leaks. When engine is warmed up, nothing will leak out. It just seems to leak out overnight when it is cold weather. I suspect it might be a freeze plug leaking. Does anyone know how hard it is to replace the freeze plugs? Is it something that a garage would have to do?
Ugh. I haven't done it yet, but this is a difficult fix. To get to the freeze plugs, one must remove the transmission. I think estimates for this fix is around $500. Knowing that little seeps out (because of the different metals, cold will cause contraction and gaps for coolant to seep out), i just keep tabs on the levels, and add when appropriate.
You can replace freeze plugs with rubber plate plugs. They consist of two plates of steel (usually stainless) with rubber sandwiched between them. A bolt connects the two plates together and when you tighten the bolt, the rubber expands out the sides, forming a tight seal. If you make sure you replace the coolant on a regular basis, these plugs seem to hold up extremely well. If you neglect the system, the metal can corrode even though it is stainless.