Gear oil for rotary mower

[seapea]

I have 3 tractor attachments (flail mower, tiller, rotary mower,) with gear boxes, and they require 3 different grades of gear oil:

Flail Mower: 75W-90 synthetic
Tiller: GL-5 85W-140
Rotary Mower: SAE 90

I’m about to change out the oil in the rotary mower and tiller. The oil in the flail mower is only a year old. For the rotary mower, I don’t see much in the way of straight up SAE 90, and what I did find all seem to be advertised for marine purposes. I’d like to use the 75W-90 synthetic I have leftover from the Flail Mower. Would that be ok? Or what about using the 85W-140 (should have enough of that left over too).

 

[tulenutn2o]

Heck, I had a seal go bad in my old 84” woods so I packed the gearbox with grease….that was 7-8 years ago. Works.

 

[scootr]

I think any one of those oils will be sufficient for all of those gear boxes.

 

[4570Man]

I’d just dump some gear lube in and not worry about it. I’ve never seen a gear box fail that had oil in it. It’s when they have no oil that the problems start.

 

[sandman2234]

Heck, I had a seal go bad in my old 84” woods so I packed the gearbox with grease….that was 7-8 years ago. Works.00

Heck, I had a seal go bad in my old 84” woods so I packed the gearbox with grease….that was 7-8 years ago. Works.

I use 00 Corn Head Grease, but now Tractor Supply has started calling it something else, but still shows up as 00. It is almost a liquid but not quite, and tends to stay in the gearbox even when the seal goes out. Plus it doesn't sling out away from the gears leaving a empty hole around the gear.
David from jax

 

[John0829]

I second the corn head grease or 00 as it is also called, it is all I use in my gear boxes new or old (mostly old). Bottom line is they just simple gear boxes that will be happy as long as there is lubricant in them, don't over think it.

 

[Kioti Dave]

I buy one pail of gear oil and use it on all my gear boxes. Can't see it being a problem.