Stemco wheel seals

[bwake]

For those that are talking about the spacer inside the hub, there is a specification for the overall length that must be measured to verify that when installed, it will keep the bearings at the proper end play setting. If it's the correct length, it will set the end play at a predetermined amount that would be tough to get exact by hand. A wheel bearing will actually last longer if there is a small amount of pre-load on it but there is no possible way for a person to test pre-load in a verifiable manner. Setting the end play to .001 to .005 gives us a way to verify the job was done in a measurable way but not to sacrifice bearing life. That's the reason for the hub spacer, it's more of a set it and forget it assuming that it's the proper length. Hopefully the pic will attach properly which shows bearing life based on end play vs pre-load.