[Eldorado]

correct, granite... what i'm talking about is the rear bearings.. front bearings are a different breed.

but to still answer your question, no.. they are not sealed bearings...

only reasons why i discussed the rears was a) it's what I have experience with, and b) you said "especially in the rear"...

but to get more to the point... when I bought the car, the car had a violent shake in the steering wheel that is no longer there. here's what I did...

balance shaft belt was off by 1 or 2 teeth... it was corrected.
front right sway bar bushing was destroyed by a leaky power steering pump.. that was replaced.
I got my wheels balanced...

just drove the car tonite up to 110mph... steering wheel felt like it was completely separate from the rest of the car. completely jitter free.

food for thought.. might not be the bearings.