ccooper

BLUF (Bottom Line Up Front): What options exist to repair wallered-out (elongated) rear upper shock mount holes?

The Story:
I've been fighting a hammering rattle in the rear of my '05 Uplander at low speeds on cobblestone roads. I am an expat living in the Netherlands for a couple years and almost all they have are cobblestone roads off of the highway. After having the van up on jacks with wheels off 4 times I finally concluded it that it "could" be the shocks. I was never happy with the auto air self-leveling system (leaks, running more than normal, etc.), so I chose to replace them with air shocks that I would set to a pressure through a external line and shrader valve (set high for a heavy load trip, otherwise keep it in the mid range pressure).

Anyway, when I installed the new shocks, I finally definitively found the source of my low speed driving hammering in the rear - the rear upper shock mount holes (opposite the threaded side for the mount bolt) were wallered out a bit and allowed the shoulder of the bolt to rattle in the hole for the slight amount of play that the shocks allowed.

For the replacement job, I wrapped the shoulder of the bold 10-15 times with some thin-gauge aluminum tape to make a poor-man's attempt at a press bushing for a "temporary" fix.

With the new shocks in place, the shoulder of the bolt wrapped to fill the waller and the bolt tightened in well, the rattle went away for about 6 weeks. It's been back for a couple months now. I haven't done anything with it for a couple reasons (and excuses).

1. The full fix would (might) require removal of the mount bracket and a new one welded in, which would require a bit of labor and I currently live in a country with extremely high costs for auto maintenance.

2. I currently depend on the vehicle as our only vehicle and don't have much leeway to go get a lot of in-person estimates.

3. The rattle is annoying, but bearable.

Also, I will be back in the states in a year, where I would feel much more comfortable checking with a local repair shop, dealer, etc. Right now where I live, the garages get ridiculous amounts for auto maintenance, their scheduling of appointments is not done in the customer's interest, and there is a lot lost in translation when all I really want to do with them is to "talk shop" a bit on the problem.

Really, I'm interested in what repair options might be out there already for such a condition. Full bracket replacement? Specialty oversized shoulder bolts? Specialty oversize bushings? Weld in an oversized washer and re-drill? Remove and re-wrap the bolt shoulders with aluminum tape every 6 weeks?

Any thoughts, from experience or just brain-storming?

Thanks!
-Coop

in2pro

welcome to the forum,
wow sounds like some auto repair fun...
I think you are right about having to have something welded in as permanent fix
thou I think you are on the right track for a quasi workable fix with washers.
If its available a combination of a good quality epoxy and over sized washers may work but I an not familiar with the scenario you are working with, a few pictures of what you are working with may help and may get input from others.

ccooper

I've attached a couple pics that might make it more clear.

By name...
"Bolt in Shock" - shows how the top of the shock looks
"Bolt Shoulder Diameter" - shows the diameter to be about 30/64in
"Bolt in Mount" - shows how the bolt goes through a first hole, then through the shock, then threads into the far side flange of the mount
"Hole Diameter" - shows to be about 36/64in

The difference of 3/32in produces quite a hammering as the bolt cantilevers from the threaded side and rattles in the "thru" side.

I tried wrapping the shoulder with the aluminum tape, but after a month or so, the rattle was back.

Any experience or ideas with this issue?
-C

Papa Bear

Are you sure you had it torqued down tight enough?

ccooper

Not positive (couldn't fit a torque wrench on it), but I tightened it pretty hard.

cooter26

What if you drill the holes out even further and make a longer sleve, one that goes thru the shock and sticks out each side of the bracket 1/8".

ccooper

Good idea, though my machining capabilities here right now are rather limited (for the new sleeve). I'm afraid I would trade one tolerance issue for a new one, in larger holes. Good idea, though and thanks for sharing. I'm trying to get a feel for my full range of options.

Anyone else have any suggestions?