Axles are pretty tough. No problem jacking the axle. Be sure hydraulic brake line is not in the way. If you are going to stick your head in or crawl under trailer, be sure to leave room to place jack stand under axle outside of your jack. Heck, if you are going to replace all those tires take it to the tire shop and let them do it. Wont cost any more and save you the trouble. Tell them not to tighten lug nuts with their jackhammer ( impact wrench) though.
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