I know some do it in the fall before they store their boat, some do it in the spring, and others do both (even though they change out lube that that was put in to store the boat but never turned on).

I read that doing it in the fall prevents storing your boat with use lube and contaminants which could be bad for it.

When do you change your outboard/inboard's lower unit gear lube?

I like to do it spring and fall.

I would do it prior to storing it. That way if there has been any water intrusion you will know and it will be ready to go in the spring.

If you live in a climate that you have freezing temps during the winter, it's best to do it in the fall before storing the boat. If it happened to develop a leak and got water in it, you risk two problems. One, the water freezing and cracking the gear case, and second, that long period between fall and spring gives the water time to rust the gears.

As for twice a year, unless it's for commercial use or you are fishing the FLW or BASS schedule, you most likely would never put enough time on it to warrant two changes a year.

If you live in a climate that you have freezing temps during the winter, it's best to do it in the fall before storing the boat. If it happened to develop a leak and got water in it, you risk two problems. One, the water freezing and cracking the gear case, and second, that long period between fall and spring gives the water time to rust the gears.

As for twice a year, unless it's for commercial use or you are fishing the FLW or BASS schedule, you most likely would never put enough time on it to warrant two changes a year.

^^ This

In the fall

Fall for me also .

Someone who changes theirs in the spring say they open it up in the fall to see if there is any water in the lower unit, and if not, they then close it up and change it in the spring. If there isn't any water coming out they're good.

 

 

If water comes out they know they may have a problem and bring it into the shop.

In a perfect world, I'd change it in the fall. That never seems to happen though and by the,time I get around to fall boat maintenance, it's too cold to drain the oil. So, spring has been it for a,while.

It's part of my late fall routine before storing it.

I change mine in the fall when I put the boat up for the winter.

 

Tight lines,

Bob

Will have to change mine before I get it out on the water.

Change the who?  The what?

In a perfect world, I'd change it in the fall. That never seems to happen though and by the,time I get around to fall boat maintenance, it's too cold to drain the oil. So, spring has been it for a,while.

Too cold to drain oil?

I usually change it in the dead of winter when I am bored.  Stored in its own garage and big door is never opened but I keep a thermometer in there.  usually never goes below 40 except when it got -30 2 years back and dropped the garage temp to about 30 I think, not sure as I was too busy with cookie pans and hair dryers unfreezing pipes in the house.

Too cold to drain oil?

Gear lube doesn't flow too good when its 30° or colder. Takes hours to drain completely.

Gear lube doesn't flow too good when its 30° or colder. Takes hours to drain completely.

Interesting, never thought of that. I haven't had that issue when it's cold though. 

I always put the ears on and run the motor for a couple of minutes. It heats up fast and I use synthetic lube which helps with draining also