Syn. oil in Twin Disc marine gear

[trawler]

I have a shrimp trawler with a couple Twin Disc 509 gears, wondering if anyone has run synthetic oil in these or similar gears.
Thanks, Steve

 

[1040 WreckerMan]

A friend had a boat that I used often and he got all my labor free. It had a pair of ZF's single speed gears that spec'd engine oil (either mono grade or multi-grade to 15w40). I ran them on syn gear oil and never had a problem. Not sure what size your Twin Disc is in comparison. But I’m not really a marine mechanic, I just pretend to be.

If the gear spec's engine oil, you'll have to run a gear oil that is similar in viscosity. If the 509 spec's an ATF (or similar) I would just run a good synthetic ATF. I should add that those ZF's leaked like a screen door on a submarine, but they weren't exactly dry on dino when they were new. Maybe someone that is more familar with marine applications will add to this.

[ May 16, 2006, 03:49 PM: Message edited by: 1040 WreckerMan ]

 

[trawler]

I should have been more specific, the specs call for a straight 30w oil, I use Valvoline Super HPO. These gears have some years on them, but I baby the boat around as much as I can. When I had them rebuilt the mechanic said they lasted as long as they did because of the tender handling.
I've run Valvoline All Fleet in the main engines for a long time. Anytime I went into one, it was pretty surprising how clean it was, no sludge or such anywhere.

 

[tom slick]

if it helps at all, 30w motor oil is about ISO 100 viscosity. It would be SAE 80w or 85w if you use an automotive type gear oil, ISO 100 if you use an industrial oil.