I am trying to replace the original driveshafts on a YRF2 which has 10x5 bearings. The shaft of all the axles is 5mm outside dia. I think 10x5 bearings are longer lasting but if you have to use 9x5 one way to alleviate the stress on them is to use a spacer between the bearings in the hub carrier/steering knuckle. That way, shocks are taken by both bearings rather than only the outside one. The downside is that stress may be transmitted to the diff if the inner swing joint makes contact with the diff screw in a collision but that is quite likely to happen without the spacer as well.
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