Immortal Gear Oil

[puckgrinder85]

There just isnt the contamination issue. Depending on the gear set "I" would change the oil out now if I were you to get all the metal out of the gearbox as the gears will wear into each other a lot at first and break-in and create a lot of metal filings. After that Im sure you'd be fine to stretch that 20 hrs. out quite a bit for sure. I know differential/ axle companies will want you to change out the gear oil the first time pretty prematurely to get those contaminants out pronto.

ps- you wont see the junk thats on the bottom from the dipstick. Stick something in there to the bottom and scrape around, will give you a better idea if there is anything. Gear oil is non detergent and tends not to suspend crap in it. It may look great because all the crud is at the bottom.

 

[Soundguy]

since most gear boxes like that don't give you good drains.. I'd wager alot of that simply stays in there forever... even inverting the bearbox / mower with solvent in it simply won't get it all out.

about the cleanest gear boxes i have seen are boxes on some john deer cutters. my batwing boxes have a square top plate you can unbolt and get in around the gear set to actually clean stuff up.. most boxes don't give you this option unfortunately..

soundguy