What is the longevity of a metal appliance hose?

Pressurized Water leaks make themselves evident with sound and if not sound the water will wick somewhere where you can see it.

If the rubber seals on the hoses were fresh (manufacturing dates can usually be determined) then you should be fine for many years.

Obviously if one’s home has gone through a M4 or greater earthquake or has structural settling problems, then the “hard pipes” in the whole house should be evaluated.

Even though they have stainless steel braid on the outside, the inside of the hose is still rubber and will rot overtime. While they may last longer than the hoses that are plain rubber I recommend replacing them every five years. I am not a plumber or appliance repair person but this is what we have been told.

We do a DIY house inspection every year looking for wear and tear on plumbing, drains, siding, foundation, anything that might need maintenance. It only take less than a day for both of us and then we can rest knowing all is well.

I changed my washer hose once in 19 years. Will check next year and replace if necessary. If normal use, they last a long time.

A stainless steel braided hose is the minimum recommended for indoor use. They are middle-of-the-road when it comes to price, but the added safety is worth the extra money. The braided stainless steel encases a rubber hose and provides a burst-resistant measure. These washing machine hoses have a lower failure rate than rubber hoses when properly installed.

Note that in tight spaces when the hose may become bent or kinked, the braided stainless steel can dig into the rubber hose.

You should replace them about every five to ten years. It's also a good idea to check the hoses for damage or leaks about every three years.