EZ Lube question

For what is worth. Our trailer has the grease fitting in the axel. The first two years I added grease per instructions before we left on a trip for the summer. The second year I lost a wheel bearing. Learned that you cannot always mix different brands of grease. Also, the beginning of the third year I removed the wheels to inspect and replaced a couple of bearings and races. I have lost a wheel bearing every summer that I just added grease. Last year I did not remove the wheels and lost a bearing. This year I removed the wheels and found three bad bearings. Also, found one seal that leaked grease into the brakes. It is always the small outer bearing that goes. I have several trailers and the travel trailer is the only one that eats bearings.