Water Heater -- Should I replace?

[flyerphann]

Wondering if I should replace my electric 50 gall water heater. It's a AO Smith Permaglas, if that makes a difference. Here's what I know:

I've been in my house for 13 years, and have had NO problems at all with it.
Looking at the decal on it, from what I can decipher, it seems like the tank was installed in 1986. Which is when the house was built.

From what I've read, water heaters can vary greatly in how long they last. Is there any way I can tell how things are going? I haven't replaced any rods/etc. Water is still clean, and warm

 

[Mr_David]

The average heater last about 8 to 10 years.
I've seen some as old as 20 yrs.
When I bought my house, the WH ( 30 gal gas) was 12yrs old.
I removed, it dragged out in the drive way, flushed it out really good and reinstalled it.
Lasted another 10 yrs before it leaked.

If yours is located inside the home with the potential of water damage, then I would replace it.
When they start leaking, they sometimes give no warning and can make a mess of things