Royal purple diff fluid.

Recently changed diff fluid after gear break in. Put in Royal purple and every time I go freeway speeds it comes out the breather and of course all over everything. I thought maybe it was overfull so I drained it in a clean pan and re filled. Just a little over 2 1/2 pints. 2.7ish I would say. Still any extended (20mi plus) over 60 mph I get it out the breather. Probably not much as it really spreads, but very annoying. I did not have this problem during break in with regular diff fluid. The only other change was PS diff covers same time I changed fluid. Axle is stk jk d44 with zip locker and 5.13's. I can see there being a slight volume difference with the locker and gear change and I am aware the fill hole is way higher on the PS covers. Questions are; Does anyone know the difference in fluid volume from stock open 3.73 diff to zip locker 5.13? Has anyone had this problem specifically with Royal purple? Is there any other possible cause? I don't mind changing fluid, but hate to waste the Royal purple if it is not the problem.

More than likely, you overfilled your diff with Royal Purple. When in doubt, you just want to have enough fluid so that it reaches the base of your axle tubes. You can use a zip tie as a dip stick to verify as much. Anything more is just too much. That being said, once you get gear oil in your breather hose, it can act as primer in a pump and will continue to pull gear oil out even if you have corrected the problem. If it were me, I would pull the hose from the axle and thoroughly clean it out from the top of the vent with brake cleaner. Then, I would make sure you have the right amount of fluid in the diff.

Did not think about cleaning out vent tube. Will do. I did the zip tie dip stick before I drained it when I thought it was overfull and it seemed fine. I have never had so much trouble with a simple fluid change. Lol!