Has anyone had a leak from their lower coolant line? Are the lines difficult to change? The line model number tag says it's: 5L1P-7F113-AA, but I cannot find on the internet anywhere. The lines appear to be rusty, so I'm guessing the seal is compremised. Is this something that I'd have to drain the coolant system before I change? Thank you in advance for the info. ~EDUB152