Customer Ratings & Reviews

If you want to keep your lower unit intact you have to either run a quality oil or change it very frequently. This gear oil gives me confidence in knowing I will be protected until my next oil change vs changing lower unit oil 4x per year with the cheap stuff.

Don’t go boating without it.

I have a 2019 Suzuki 90hp and a 1994 Mercury 115hp and use Amsoil gear lube in each one. Thanks

I absolutely love this stuff! Why would you ever want to put "good enough" products in your investments when you can use "the BEST" for often times cheaper. Worry free with this stuff and ALL Amsoil products!

I switched to amsoil Marine gear lube full synthetic had been using Quicksilver or Mercury Marine 75/90 w in the past but the reviews for amsoil full synthetic surpassed all recommendations so I changed it this fall and we'll see how things go in the spring 2026

im a certified marine tech and i use that oil in all lower units, volvo, mercruiser, mercury, johnson, evinrude, honda, ect

Put this in an older outboard I recently got, shifting is quiet and smooth

I don’t know how to review a marine gear lube. I am hoping the good people at Amsoil make a good product, but honestly, I have no way of knowing for sure. However, the packaging is the best compared to other bottles of gear lube I have used. It made filling the gear box much easier and for this I gave 5 stars.

At first appearance this product may be mistaken as just normal gear lube. WRONG, it takes a chemical to remove from your hands so just imagine how well it is protecting the internals of your lower unit! Will use as long as I have a boat! Amsoil rocks!

Brand new 2025 Mercury 90. Peace of mind now that break in is complete and Amsoil is in. c”,)

Was a little skeptical on the squeeze bag, but after using it in a couple of lower units now, I dont see myself going back to the pump. I can squeeze out the air, pop the cap back on and stick it on the bottom of my toolbox. With preferred pricing and free shipping pricing is competitive with big box store, for what I believe to be a superior product.

Best product on the market for marine lower units. The unit on my older boat had gotten to chattering and it quietened it down perfectly.

Have owned my boat with Honda BF90 outboard since 2004. Every year I change the main oil and gear lube with AMSOIL. Have not had any mechanical issues ever and the engine has been in the shop only three times in twenty-one years for tune-ups. Only use AMSOIL products in everthing I own.

Great blend, easy to use container. Awesome.

Never used AMSOIL products before, but found that the gear oil for my Volvo Penta outdrive required 75w90 without limited slip additives and AMSOIL sold it. The price was a bit better than the VolvoPenta packaged gear oil, so I thought I’d try it. AMSOIL claims that it still functions with up to 15% water in it, and where this outdrive is new to me, I’m not entirely sure it’s water tight. We’ll see at the end of the year when I drain it.

Switching both of my Suzuki outboards over to Amsoil products, as I use their products in everything else. Great products, with a great pricepoint program, and very fast shipment for me here in WI.

This is my first year trying the full synthetic gear oil, and the first thing noticed was how much smoother my Bravo One XRs are shifting. I have already recommended this product to my boating family.

Been running this in the lower unit of my Suzuki DF50 since I took the break in oil out. It gets ran had either wide open up the Missouri River, long idle/ no wake zones, and sometimes run in the mud while duck hunting. So having an oil that protects the lower unit is crucial since my sees a lot of abuse being a hunting and river boat. My lower unit shifts better than when it was new and is quiet and vibration free.

have been using this product for years and I'm very happy with this gear lube. It says what it supposed to do easy shifting and no ware on the parts even if water does penetrate the system. when I drain the lower unit there is no metal filings on the drain plug that tells me it is doing its job.

Use this in my Yamaha F115, about 100 hours per season. When replacing the marine gear lube in the fall, it comes out yellow as I had just put it in !