Lower unit oil change needed?

[Jonross227]

Did the maintenance on my Yamaha 250 SHO on Feb of 2022 with Amsoil Marine engine and gear lube. Due to work and other complications I only put about 6 hours on the boat in 22 & 23 combined.
This year I'll actually be able to fish again starting with a week long vacation.
In preparation, I'm going to go ahead and change the oil, filter, and fuel filters but I wondered if I needed to or should change the lower unit gear oil as well since it has minimal use on it.
I'll be doing the water pump later this year at which time I'll drain and replace the gear oil.

 

[ls1mike]

Do it! I had a leak in mine where water got in and I was unware. Locked the lower unit up. Had to replace it. I now change it every 5 outings and before I put it up for winter. It is cheap and easy insurance.

 

[Boomer]

How are the seals? Did you find water the last tme you changed it? If so, change it again.

 

[Donald]

While the gear oil has lots of life, the best practice is to change it yearly and evaluate for water. A seal could be damaged with 1 hour on the gear oil.

 

[Gillsy]

Gear lube is cheap compared to a lower unit rebuild. For piece of mind, it's a no brainer.

 

[Big E]

If I didn't put many hours on my boats during the season, I would just loosen the drain plug with the fill plug still tight. A small amount will come out. Easy to check the condition of the lube visually and if there's any water inside it should settle to the bottom and come out first.

Never had any issues with my OMC and VP outdrives.

If it keeps you up at night, then just change it.

 

[Snagglefoot]

I’ve been guilty of poor boying it. I’d let it sit for a few days in the fall, then remove the plug and drain any water. Then I’d inject enough fresh lube to top it up. Good for another season.

 

[another Todd]

Lower the drive and remove the bottom drain plug only for a second or two, and see what comes out. It should be clean gear oil with only 6 hours. If there is any hint of liquid water or water oil emulsion, change it otherwise change it when you do the water pump...good idea to pressure and vacuum test the lower unit while you have the oil drained to ensure the seals are in great shape.