I'm not sure on the price but it should be pretty cheap. It's easy enough to do. You might have to drain the rear end to keep the fluid from comming out the seal while your changing it. Don't use an impact on the pinion nut when you put it back on either. You can damage the pinion bearings. Some extra insurance agianst leakage is to put some RTV on the pinion flange where it contacts the pinion shaft (ridges). I had fluid leaking from there and not the seal.
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