gearcase oil

[snopromoe]

what is a good oil to use in oil pump gearcase. the shop manual says a non-foaming type  and the guys down at napa just get a blank stare

[tomahawkcat]

penzoil makes a 80 weight that works good come in a tall yellow bottle no to bad in price. called a gear lube 

[Invader440]

I use 5W30.

[Mad Kaw]

pretty sure all engine oil is non-foaming these days

a guy at napa thought i was nuts when i wanted "two sets" of small block chevy exhaust manifold gaskets... at first it was "you want both donuts?" then it was,, "theres enough for both sides"... i finally had to tell him that the gaskets are cheap and you have to double them up otherwise they'll leak... 

"well why dont you buy good ones then?" dude,,, because they're for a boat and these slip in from the top and im not contorting myself for 5 hours to take the manifolds off when i can have it done in 15 minutes sitting on a seat... so just give me 2 sets 

[mswyka]

I use whatever automobile engine oil I have on the shelf.  10W40, 10W30, 5W30, 5W20.   They all work.

[Lloyd (ljm)]

 I always use ATF. Works good

[Tory944]

Going by memory, I believe the shop manual says 10w40....

[snopromoe]

  well thanks guys that really narrowed it down LOL. 80 weight gear lube is much higher in viscosity than 5w40 but it also sticks to the gears far better. i will try that

[mswyka]

well thanks guys that really narrowed it down LOL. 80 weight gear lube is much higher in viscosity than 5w40 but it also sticks to the gears far better. i will try that

Yeah, it will stick to the gears, but if it gets cold it may not provide the lubrication that the bearings and seals really want to have until after the gear case fully warms up.  If it was a lower speed unit it probably would not matter, but spinning 6,000 to 8,000 rpm my recommendation would be to stick with the motor oil.

[snopromoe]

yep motor oil sounds like better bet now. HMMMMM! donuts now i want some