Front axle Lub

[retired farmer]

I drained the front axle of factory lub and refilled per operating manual. I put in four quarts of 90 wt. gear oil. According to the book it holds 4.8 US qts. It appears to need more to be full. Question is; is it ok to top it off with SUDT as I have a couple gals. left in my stock or should I get another qt. of 90 wt. gear oil?
rr
I might add this is a L3301 fwd.

 

[jyoutz]

The service shop where I bought my tractor said it was approved to use either gear oil or SUDT, but not to mix them.

 

[mcfarmall]

My manual says both are acceptable with no warnings about mixing the two.

 

[cthomas]

Is it full? It would take a long time to completely drain it. On vehicles I have left a rear end cover off overnight and you can wipe more out of the rear end. What is a L3301 fwd? I have heard of the L3301 but, fwd in my book is Front Wheel Drive. I would get another quart of gear lube, so next time it is changed it will be almost 100 percent gear lube. Of course I can find gear lube at work, but, no SUDT is floating around.

 

[The Evil Twin]

It won't hurt anything. Since you drained out SUDT2, it's already mixed in there anyway.

 

[DustyRusty]

A lot depends on where you live. If you are in an extremely cold climate, the 80/90 gear lube isn't going to lubricate the universal joints in your front differential very well, since it will be as thick as glue when the temperatures are below freezing. If you live in one of the warmer climates then it doesn't matter what you put into the front differential. Your profile says " From sheridan". There are 23 places named Sheridan in America. Pick one.

 

[North Idaho Wolfman]

If you used straight 90w it's too heavy!
Mix some SUDT2 in with it to thin it up a little.

 

[The Evil Twin]

A lot depends on where you live. If you are in an extremely cold climate, the 80/90 gear lube isn't going to lubricate the universal joints in your front differential very well, since it will be as thick as glue when the temperatures are below freezing. If you live in one of the warmer climates then it doesn't matter what you put into the front differential. Your profile says " From sheridan". There are 23 places named Sheridan in America. Pick one.

You bring up a good point. Gear lube limit is 10°f above its pour point. 80/90 gear oil has a pour point of (let's just use Valvoline) of -30°f. The service limit should be around -20°f. If it's colder than that where you live, use SUDT2.

 

[retired farmer]

You bring up a good point. Gear lube limit is 10°f above its pour point. 80/90 gear oil has a pour point of (let's just use Valvoline) of -30°f. The service limit should be around -20°f. If it's colder than that where you live, use SUDT2.

Thanks for the replies. There will some SUD left in the axle after draining, even overnight as I did. So I figure a little more mix won't hurt a thing. Cold weather not a problem here way down in AR, most of the time. If it's below freezing I have the option of staying by the fire.
rr