I got a chance today to see what all the noise was in the rear end.As I took off the hubcap it was very clear what had gone wrong.Are you ready for this,loose lug nuts,duh!When I changed over to snows a few days ago I used my electric impact gun to remove and install the lugs.As a rule I never use it to tighten the lugs for fear of having them too tight.So it looks like I did not tighten them enough to begin with.The rim is toast,the holes are oval.All the lugs wil have to be replaced.Had I driven maybe 10 more miles they would have surely snapped.The good part is each lug is so close to shearing that I could snap them with a pair of pliers then tap them out.The install will be a different story,maybe someone has a tip for me.
So if you hear a clunk,rattle in the rear and you recently removed a tire for whatever reason,check the lugs first to make sure they are tight.
Thank you all who replied to my post.Looks like the 87 240 will get the new radio after all.
Nelson