Gear Box

I drained the gear box from my 74 850 Commando I bought to settle an estate. To my surprise automatic transmission fluid came out, the manual calls for 90wt. ATF is only 10wt. I have never put ATF fluid in any gearbox in my 40 yrs of working on bikes. BUT since this is the first Norton I`ve ever owned I thought I would asks you Norton gear heads.

Ride Safe

ATF is decades long upgrade lube in AMC gear boxes and primary chains, but only really helpful over plain gear lube if much time at rpm limits in lower gears the sleeve bushes starve till oil dry into ceramic grit instead of lube. ATF helps to ID leaks better too. In other words its a non issue with some points in favor of ATF.

Like hobot says, ATF does work just fine, however there is what seems to be an ongoing debate on this forums about ATF or 90w. Heres some threads

gearbox-lube-apologize-t8252.html?hilit=atf

this one has info about ATF on the second page, it seems to have more of a negative outlook on ATF, however I still havent heard of anyone using ATF that has had problems

gearbox-will-shift-down-not-t8207-15.html?hilit=atf

Gday All, the standard ATF oil in cars is a 10 grade, but you can get multigrades or straight slightly heavier if you desire. Multi grades as follows; 5w-30 ; 10w-30 and striaght 30 ; 50 and 60. The discussions on oil is endless..........
I probably will use the same oil I use in my 350 HP tractors, sold as a 10 but it specs out at 30. You could also blend your own maybe mixing 50/50 of both gear and ATF if you think 10 is too lite?
Foxy

Thanks for the reply everyone. I didn`t know that AFT could be used in any gear box. But after reading the links I can see that it`s definitely something worth considering.
Also you are NEVER to old to learn something new. I thought the previous owner didn`t know what he was doing buy using ATF. Thanks to all!

Many also light ATF in their forks but I prefer power steering fluid now.

hobot said:

Many also light ATF in their forks but I prefer power steering fluid now.

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I thought they were the same viscosity ?

Cash