Jim:
Dunno if you got a reply or not. So here goes...
Let me say that I have not dealt with this personally, other
than to disassemble my trailing arms and rebuild the hubs and replace
U-Joints. The studs on my car were in perfect shape. My only precaution
when reassembling was to locktite the studs in place. My reasoning was
like this - You cannot tighten the studs because that will stripe out
the threads. Leaving them loose will allow them to move around, which
will eventually pull out the threads as well. So I loc-tited them all so
that they could not move, without the need to over torque them.
1. Coarse threads will be stronger than fine threads. If your PO
had not helicoiled everything already, I would say the simplest upgrade
is to helicoil all the studs with 5/16" coarse thread.
2. Checking them for security is best done by making sure they
are torqued to the factory spec (assuming they are stock). If they are
loose, they will certainly fail eventually, and if they cannot reach the
specified torque they have already failed. Unfortunately, the factory
torque setting is too low to guarantee stud retention, and they cannot
be torqued high enough to insure they will not loosen again.
3. OK, lets say they have already been helicoiled, and have
subsequently failed. You have a couple of repair options:
a. http://www.aluminumrepair.com These guys offer an
alloy that can be melted into place and then drilled and tapped, or you
can cast a stud directly into the repaired arm. The melting point is
fairly low, and it looks like you can use a propane or perhaps MAPP gas
torch to do the repair.
b. EZ locks. http://www.nutty.com/threadrepair.shtml
These are beefier alternatives to helicoils.
c. Threadserts http://www.nutty.com/threatsert.shtml. I
personally would not use these as they have no positive lock to the
metal, relying instead on a sort of press fit. Seems like they might
pull out - but that s just a guess on my part. Other listers may have
had good experience with them.
e. Drill and tap to the next larger size stud. This will
require modification of your hubs, but this may not be a problem for
you. I would once again recommend coarse threads rather than fine
threads in aluminum.
Cheers,
Vance
-----Original Message-----
From: owner-6pack@Autox.Team.Net [mailto:owner-6pack@Autox.Team.Net] On
Behalf Of Jimandruthhome@aol.com
Sent: August 20, 2007 2:45 PM
To: 6pack@autox.team.net
Subject: [6pack] trailing arm studs
Hi,
I know this issue has come up before, but I always thought, "never
happen to
me" so I didn't pay close attention. Well, it happened to me, driving
down
the Garden State Parkway headed for a week at the shore. Fortunately,
the
lower studs had only pulled partway out when I noticed excessive camber
on the
RR wheel after arriving in Cape May.
<snip>
What is the best way to check the studs for security.
What would be the best approach to strengthening the hold that the
studs
have in the aluminum?
Is there a better thread replacement than helicoil, or one that will
work in
a hole where helicoils have pulled loose?
<snip>
Thanks in advance for any advice the list can offer,
Jim Knight
_jimandruthhome@aol.com_ (mailto:jimandruthhome@aol.com)
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