First let me say thanks for all the assistance I've received on this
board. It has been invaluable and I hope others learn from my
experiences/mistakes also... :-)
So the Suburban, she thumps, but only when I let off the brake
(medium-hard braking). I've taken it to the local shops but no help.
Everyone feels it, but no one can pin point it. First they speculated
drive shaft, then tranny mount. I couldn't figure why they'd be
looking there but "they're the experts"... In the end, no true source
of movement was found.
I then looked at the suspension. I found a bolt missing from the leaf
springs (it's a U-bracket that surrounds the leafs), replaced it, no
help. Figured I'd live with it for a while to see if something breaks
or becomes more obvious.
Then I noticed my tires were worn and needed replacing. Didn't give
it much thought as they looked like dry rot had set in but I did take
notice that they only had 10k miles on them. They were purchased from
tirerack so I figured they just weren't a good place to buy tires.
The next set I bought from Discount Tires and then had it aligned.
Now 2k miles later, the right front is showing signs of obvious
feathering. The left could also be but it's definitely not as
noticeable. I can't help but think that the thump and the feathering
are related. I checked the toe-in and it's set at 3/4". Seems close
enough so my theory is that something is moving and causing the
alignment to change but then resets such that the alignment goes back
to normal after letting off the brake. I don't feel the steering
wheel move when it happens though.
I've lifted the front and tried to shake things about but nothing
gives. I only weigh 150lbs so I'm probably not big enough to do any
meaningful shaking but I tried... ;-) Using a tie-strap w/ rachet I
was able to get the steering links to move about 1/4" front to back
but again I'm not finding any true source of movement.
Any thoughts? Should I just sell the damn thing? I can't afford to
be going through tires every 10k miles...