The right amount of diff fluid?
 

Hi Everyone,

Can anyone explain how to figure out the right amount of differential fluid when you have a special application?

I've got the mag-hytek cover and a lift kit with blocks that rotate the axle housing 15 degrees. Because of that, I figure the marks on the hytek dipstick are probably useless. I've also heard people complain that the specs on the hytek cover might be off a bit for our axles.

After a recent trip, I noticed that I'm pushing fluid out of the vent tube on the drivers side of the truck, so I feel safe in saying I've got too much fluid in the rear diff... :)

Have I done my diff any harm in being overfilled? Any advice on how to figure out the right amount? Maybe I should just let it come out the overflow tube until it stops?

Thanks for the advice!

The only harm could be that as the gears "whip up" the fluid and expel it... it gets air trapped in it and it is unable to lubricate fully as air is not a lubricator.

I would think that as it expells from the vent, that it would level off and stop. I would also call MagHytech and ask them what their thoughts are for lifted trucks with rotated axles... surely your not the first person to encounter this?

Good luck,

Check out an unmodified truck and see where the fill plug is in relation to the axle shaft. Usually the bottom of the fill pulg is just about at the top of the axle.

Once you have that relationship, fill to the appropriate level and see if you have any oil leaking from the vent.

Lou Braun