I seem to go thru them about every 3-4 years. Do you have this problem?

Indefinately. They've even survived craching into the deck after being knocked off the transom. What brand? Airmar?

Huh, I've never had to replace one yet, I ppaint it with fresh transducer paint every year.

Given the rate at which the technology is changing, I would probably want a new fishfinder and transducer every 3 or 4 years anyways.

I've only had to replace one and that was after about 15 years.

The reason I ask is that the transducer on my downrigger is dead and I called the company and they said "You should only expect about 3 years out of a transducer as the this the life expectancy"
Really, I said? I thought they last forever unless damaged.

So I replaced it with a new one and the other day I had some problem with the transducer on my main unit which is about the same age. This is an airmar tri-ducer depth, speed and temp, the speed and temp work but the depth was flaky. I scrubbed it off checked all the connections and it didn't do much. Came home, ordered a new one. This AM it worked great, didn't miss a beat even at 30 knots :uhoh: I will be going out again later this afternoon and will check it out in some deep water. Maybe it was just a hickup in some software. First time I ever saw a problem with that though.
In a week I will probably be the proud owner of a spare transducer.:uhoh:

After this thread, I'm thinking of getting a new one. Temp is good, depth is good other than an occasional hickup which quickly resets itself but the fishfinder always brings up fish that are not there. Unless I have been surrounded by fish everytime I go out and can't catch any of them!! which could be possible. I think the transducer is about 7yrs old. It came off an older Garmin unit and I just upgraded to a 498 and kept the same transducer which their tech group said would be fine.

but the fishfinder always brings up fish that are not there. Unless I have been surrounded by fish everytime I go out and can't catch any of them!! which could be possible. \

Do you have one of those machines that shows little fish pictures instead of the actual echo return? If so it's probably not the transducer, those unit get fooled all the time with seaweed and other debris passing under the boat.

I thinkmy transducer is fine. I think it had a hicup of somekind but when the power was really turned off (ie battery switch to OFF) then upon restart all was fine again. I have one of those black box units and if you just turn off screen the black box is on but flashes that the main unit is off. The black box is ON as soon as any battery is on. So after the power was cycled it worked fine all day today, in fact better actually, I think the problem was marine growth on the transducer itself. (I don't paint it)

Mine shows the fishes. Although it is a brand new unit from Garmin just released this spring. Not sure if that matters. Hopefully their technology has evolved to be a little better than that of 7 years ago.

my works fine... accept after about 6mph it just starts marking fishleft and right... what a %^& tease. its just the water disturbance, i don't think there is any way to fix that.

Mine shows the fishes. Although it is a brand new unit from Garmin just released this spring. Not sure if that matters. Hopefully their technology has evolved to be a little better than that of 7 years ago.

The replacement transducer is the same as the one you have. You can get a much better transducer but it will cost more than your FF.

Your Fish ID function will show you all the fish, and also show most of the debris as fish. There's just too much stuff in our waters for it to work right. Turn it off and go for a ride with someone that can tell you what the marks mean.