How many of you use straight 30? Where are you using your vessel? How many of you use straight 40? Where are you using your vessel? Thoughts on either weight- do you change when the the water gets warmer?
NAPA part number 75118. 5 gal pal of CF-2 / straight 40W oil. Perfect for any TD or big ZF south of the Mason/Dixon line (30W north). BTW, same oil for your DDCs.
I use Straight 40W always. I even used it in a yacht I did the Great Loop with that saw ice on it's bow two mornings in a row. If you're letting the engines warm up for say 20 minutes, in most cases that will warm up the gear oil temperature too as you have sea water passing through the gear lube oil cooler which is warmer than ambient air in colder climates usually........
I've never seen a twin disc plaque state anything but "30 SAE"; I've heard of folks who assume that the heavier oil is okay in warmer climes and used it without issue that manifest themselves immediately. I have not searched nor found anything which backs up that assumption and I wanted to ask here. I'd love to hear from more members.
The model tag is all I have found. The catch-all TD owners manual does reflect another tag similar to the second example I have attached. Interesting. I have never found a oil spec plate on the TD clutches I have looked after. I have worked side by side with TD Southeast techs pouring 40w in various clutches. When I get back in, I'll try to find some model specific data. Bamboo, is there an exact model your asking about/for? I do know, ZF does spec 40w in a operating temperature graph.
Here is a Twin Disc marine gear owners manual for a marine gear. In section 2-3 it recommends 30w,40w, or 50w and even 15w-40. Not sure if it's the correct booklet for the gear you have. http://www.twindisc.com/wp-content/...-Trans-Owners-Manual-1016313_RevH_0116_CD.pdf See figure 5.2 on page 5-10 shows a chart for temperatures and SAE 30W and SAE 40W for many (possibly all) of the Twin Disc models. The other models shown on same chart have a temperature chart for either SAE 40/SAE50. Looks like some models use 30 or 40w, and others 40 or 50w, but can use 40w in all.
No specific model; just asking because there is book knowledge and there is real world what people are actually doing information which is found less often in books. Because my individual experience is just that- individual- I'm asking here. One of the last vessels I was on the gear listed "SAE 30" as the oil and I've always used that on TwinDisc and haven't heard of SAE 40 or other weights used on a regular basis. It certainly appears SAE 40 is used widely.
I use SAE 40 and have for over a decade on all gears, unless the gear asks for something other than conventional oil, like some of the smaller v-drives calling for ATF etc.
My Man engines and ZF350 trans both came with the same 5-40w Delvac 1 Mobil One. After using that for the first 4 years I converted to a straight 40w for the last 4 yrs in the ZF's. Have not noticed any difference except in the pocketbook. Still using Mobil One Delvac 1 5-40 in the engines.