Hypiod Lower End Gear Oil

[barnesrobe@gmail.com]

The specs in the manual state to use GL-5 Hypnos oil but that is difficult to find. Can it be any marine gear rated GL-5 such as synthetic or high viscosity or does it have to be hypiod?

[Harper]

Any GL-5 marine gear lube is acceptable. I personally use Amsoil.

[tsturm]

The specs in the manual state to use GL-5 Hypnos oil but that is difficult to find. Can it be any marine gear rated GL-5 such as synthetic or high viscosity or does it have to be hypiod?

I have used any 80-90 gear oil for the last 50 years (except the OMC electro shift) if you don't have leaky seals you don't need "Marine" gear lube

[briscoe]

Barnesrobe, it is difficult to find GL5 in 90 wt. It's pretty expensive too. However, I used Amsoil 80W-90 and the gears wore out before I could change the oil again. Bite the bullet and buy 90 wt. GL5. Yes GL5, is a hypoid oil but it is very different than motor oil, however WT matters! Viscosity matters! You can get from Amazon. Move along little doggie, order today and change oil in 2 days.

[barnesrobe@gmail.com]

Barnesrobe, it is difficult to find GL5 in 90 wt. It's pretty expensive too. However, I used Amsoil 80W-90 and the gears wore out before I could change the oil again. Bite the bullet and buy 90 wt. GL5. Yes GL5, is a hypoid oil but it is very different than motor oil, however WT matters! Viscosity matters! You can get from Amazon. Move along little doggie, order today and change oil in 2 days.

OK, just to make sure I understand… any marine GL-5 SAE 90 is fine even if it is not specifically “Hypoid”. I did order Hypoid GL-5 on Amazon but it might not arrive until November which is a tad late.

I am looking at Star brite 027232C Synthetic Blend Lower Unit Gear Lube, 80W-90W-946ml.

[Harper]

Barnesrobe, it is difficult to find GL5 in 90 wt. It's pretty expensive too. However, I used Amsoil 80W-90 and the gears wore out before I could change the oil again. Bite the bullet and buy 90 wt. GL5. Yes GL5, is a hypoid oil but it is very different than motor oil, however WT matters! Viscosity matters! You can get from Amazon. Move along little doggie, order today and change oil in 2 days.

Hmm. I've been running Amsoil 80W-90 for 12 years and never had a problem. Lower unit was apart for seal replacement this year and showed no unusual wear. Dealer refilled with the prescribed 90 wt , because that's what he uses, and of course, I'll keep that in till next change.

[briscoe]

As is said, I used Amsoil 80W-90 gear oil and when my lower started making g crazy noise I drained it and the entire prop gear teeth and the driveshaft teeth were ground down to fine dust. Amsoil said they would replace it all, but dealer reminded me I had purchased additional 5 yr protection, which they used instead. Just sayin, I will NEVER, EVER use anything but 90wt gl5.
I didn't mentionmention my last trip, before failure, I was running with a particularly large fellow in boat. Had to put him in front of console to get on plane. Even so, the oil should not have failed. Hypoid gears are one of the reasons wind turbines are so problematic. The trickiest gear to lubricate, I've heard.