I have a 98 F150 XL with the 4.2 6 cylinder.  I have the beginning of a
serious problem.

I believe my rear end is falling apart! The truck has worn out a set of
Goodyear Wrangler RTS tires in 20,000 miles. They developed dips or low spots
in the tires. I have had the shocks replaced, front end checked out, put new
tires on the truck 2 weeks ago. Of those items there is nothing wrong. At 50
miles per hour or more the truck vibrates. I had a front end mechanic look at
the truck today and he said the front end was fine. But, he had the truck up
on a rack and the tires free. He put the truck in drive and ran it up to 60
mph. The truck vibrated and you could see the rear wheels moving back and
forth. (About a 1/2 " movement. ) You could also hear a bumping type noise in
the rear end and the casing was very hot.

The mechanic said this was a bad problem. Is this true? Has there been a
recall on the rear ends on this truck? He also said it would cost me as much
as $2000.00 to replace the rear end at the Ford Dealership. Does this sound
right?

Your response is appreciated

Bob