The recent post prompted me to ask this: I recently replaced the rear hub seals on the 57 GMC 2 1/2 ton, with the T150 rear axel
I got the seals from NAPA, part number nos162. On the box it said it included SKF's patented speedi-sleeve kit. It was only a small plastic looking ring, nowhere near as large ID as the main seal. It looks to be near the same size as the axel end where the big nuts go. There was no instructions and the counter person did not know what it was. I installed the big seal in the hub. But would still like to know what the other part was for.

57 GMC LCF 370
55 John Deere 40-W
59 John Deere 430-W
2000 GMC 4x4
56 John Deere 420-W
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