I put my thumb over the hole and use the squirt tip on the bottle to get 5 qts in and I over fill so it WILL get oil to the brgs. No problem with leaking seals cuz they get lubed and cooled too. I had an earlier Dodge when they had a lot of axle seal problems - dana80. Right after I had mine warrantied I put in a 3/4" street 90 and filled it up. No more seal problems. How do you think OTR trucks do it? It's not really over filling - it's more like running the oil level where floating axles are supposed to have it. Craig