A friend has a '98 2500 RAM Turbodiesel... the steering wheel has always had
a little wobble, but lately it's gotten pretty severe! The truck steers OK,
and the wobble seems to be isolated to the mechanism just beneath the
steering wheel itself. We pulled it this morning and couldn't see anything
specific that was broken (other than the casing for the clockspring
electrical connector!)...

At the dealer, they couldn't find any diagram of internal parts in the
steering mechanism that would be servicable, and could only offer a new one
(at $1500)...

Anybody have any experience with similar problem? Is it likely we can tear
it apart and rebuild it? ... an alternative is to check a Pull-a-Part lot
for a replacement, but is there a good chance it will have a similar
problem?....

parrot33 at hotmail dot com

A likely cause of this is wear in the U-joints of the intermediate shaft.
This is the shaft that runs from the bottom of the steering column, through
the engine compartment, to the steering box. Grab ahold of the intermediate
shaft, and see if you can twist it back and forth a little (with the
steering wheel locked, or someone holding it). If you feel any wobble, then
you've found your problem.