How do you tell if your caulking is failing?

[fivecodys]

This sounds like an easy question but the more I thought about it the more I scratched my head.
Roof caulking was easy. Look for cracks. If it's cracked it needs some attention.
This is easy to see since most runs of the sealant are very wide.
But how about the caulking on the sides of the trailer?
What, in your opinion, should I be looking for?
I typicaly look to see if the caulking has started to pull away (shrink) from the windows, refer service panel, seams ect.
Is this the right way to determine failure?

I need some advice please.

Many thanks!

Bill

[fivecodys]

Thank you all for your comments.
It was very helpful.

Bill

[da_bees]

Your method sounds ok to me. I would only add aligator cracking. Real failures are usualy due to improper installation of window or other item. If it leaks,caulking alone usualy isn't the fix. I feel safe in saying that if every trailer in a campground that had been caulked after leaving the factury was inspected,more than 50% were done improperly.
Not removing old caulk and cleaning the joint is most common problem.

[deleted-2]

I'm gonna say caulking failures are probably few and far between.
Seen some caulking that looked like hell...yet never leaked at all.

Any leaks I ever had were from damaged roof rubber or cracked vents, covers or dried out glazing bead .

[broark01]

Take your finger and try to gently roll the edge of the caulk on the trim or trailer away from the trim or the trailer to see if it separates, it should be stuck and take considerable effort to separate it.

[donn0128]

Same thing. Cracks means a potiential leak.