That price seems kinda high..or maybe not. It's an easy job to repack bearings and adjust brakes. You may have the EZ Lube type axles and so a re-pack could be done with a jack and a grease gun. Certainly your brakes need adjusting, really bad. But, that is even easier to do. Some people are more comfortable pulling the hubs and repacking the old school way. That would require replacing the grease seals. Some folks try to reuse them but, they are so easy to damage that I'd would always replace them. If you get the business apart intending to reuse the seals and then booger them up you're stuck till new seals can be obtained. My Coleman has the Lippert EZ lube type axles. The engineers designed them to be "re-packed" without removing the hubs. Jack them up, connect the grease gun, spin the wheel and squirt the grease. Not difficult at all. But, repacking doesn't need to be done very often. I'll bet with only 3000 miles and 4 years you don't need a repack. But, I'd definitely not pull that trailer down the road with adjusting those brakes.
I cannot jack from the frame rails as the LP gas line runs down one of those. I put a jack under the "U" bolt on the axle and lift the tire up enough to get the job done. Do not put a jack under the axle it's self. It's hollow and can be damaged pretty easy.
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