My truck 01 cummins has been sitting 2 days with block heater plugged in. I'm out side today and I look over and witness a leak just start and drip a good sized puddle. So I investigate and it's coming out of the cap on the power steering. I took off the cap and it's over flowing. Any ideas?

What color is the fluid? Did it look like engine oil black or more on the clear side, check your brake reservoir oil level as well.

how cold was it out? if it was below freezing you may have water freezing pushing steering fluid out?

Think a bit differently when was the last time you changed the power steering fluid and flushed the system?

When it got really cold last year the same thing happened to me. Pushed out a fair amount of power steering fluid. Just topped it back up when the temp warmed up a bit. It didn't do this until it dipped below -30 though. was kind of weird.