Well, to be honest, the caliper has to come off if you want to replace the seal properly. There is a shortcut, but this involves cutting the seal and rejoining it, but that's not acceptable IMHO. Otherwise you will have to pull the half shaft, which can be done by loosening the seven bolts that secure the swivel housing to the axle. That way, you don't have to pull the hub off, but I would certainly do it whilst being at it anyway, unless you did the hub and bearings recently already. The work is not rocket science, just takes a little while and is rather messy, but then you know it's done and won't have to worry about it for a while.
As for replacement of the bearings, well, depends on when they were done last time. Timken has increased the prices but if you can afford it, I'd swap them anyway. Did mine recently, was well worth it.
Cheers
Johannes
There are people who spend all weekend cleaning the car.
And there are people who drive Discovery.
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