My SDL not only has the original head, which are well known to cause problems if overheated. It has the original head gasket which I think is pretty amazing since those are a weak point, on not only these engines but several other MB I6 designs.

I can honestly say I don't give it much thought or worry.

You could go out and buy a late model Toyota tomarrow and the next day the trans could blow up.

If it blows fix it, until then drive it. It could be nothing, you simply do not have enough info at this point to come to a conclusion.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200