Recently replaced a front wheel hub on a 1999 Bravada. When I pulled the hub off the axle, I noticed the o-ring looked tired. I reassembled the vehicle using the old o-ring. A week later I replaced the ball joints on the same side I replaced the hub. When I repulled the hib, I noticed the o-ring looked even worse. I searched Rock-auto for a replacement, but no luck. I next searched Autozone, Orielly and Advance Auto. No luck, not even listed as a part. Did more checking and noticed that if you but a Timken (which I did) or a National, no o-ring is included. If you but a AC Delco hub, it comes with a new o-ring.

Did more research and discovered this o-ring is often associated with erroneous ABS errors, and to lube the o-ring prior to install- which I did with Mobil 1 synthetic lube. More research and I discovered a seller on E-bay had the o-ring and also listed the OEM part number. Then did a search on Rockauto and discovered they can get the part with a 5 day wait for only 4.38 ( I bought 5). It is interesting that Rockauto lists this part as for "no-vehicle" and list no internal Rock-auto part number. In case anyone ever needs one of these here is the ordering info:

ACDELCO 290302 (290-302) Wheel Seal $ 4.38 $ 0.00 5 $ 21.90

Good info! thanks for sharing it will sure prevent a few headaches

Thanks for taking the trouble to dig that info up. I'll have to save your post for future reference when I do my Blazer.