Thanks Dennis. That all makes sense.

On my '81, a while back, I did a bunch of front end work. Ironically I
replaced the lower control arm bushings and repaired/replaced the radius
arm bushings.
https://sites.google.com/site/tubaneil2/vanagonmaintenanceandrepair

But....

While doing the work, with the UCA freed from the UBJ, I recall only moving
the arms up/down and left it at that. Took the van to the alignment shop.
They kindly let me know about the UCA bushing wear:

"They are starting to go".

The bushings weren't  *that* worn as the frame holes and long bolt were ok,
and the van still drove straight, but over the next while, (1-2 years?)
this play likely caused a little premature uneven tire wear.

https://picasaweb.google.com/musomuso/YokohamaTireWear#5597083935736325698

If I'd taken time to thoroughly check for bushing wear (3 & 9:00 movement),
I would have saved on another alignment and likely some tire wear.

Neil.

On Tue, Aug 28, 2012 at 3:32 PM, Dennis Haynes <d23haynes57@hotmail.com>wrote:

> Yes worn and damaged bushings can cause alignment changes after the fact.
> The upper control arm bushings as you noted are a definite problem. As the
> arm changes position both camber and caster are affected. Probably the most
> important and often overlooked are the lower control arm bushings and the
> radius rod (strut) mountings. Keep in mind that as part of the suspension
> operation these rubber parts do flex with load changes. Also for the best
> alignment the vehicle should be loaded as it is usually used. Even the toe
> angle will change with vehicle height as the control arms pivot changing
> the
> distance between the wheel spindle and the rack. I like to even have
> someone
> in the driver's seat during an alignment.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> neil n
> Sent: Tuesday, August 28, 2012 3:11 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Was: Tire Wear.. Now: Worn Upper Control Arm Bushings - Alignment
>
> So Jack's question and this samba post (here;
> http://www.thesamba.com/vw/forum/viewtopic.php?t=525738   )  got me
> wondering.
>
> AFAIK, if ONLY the bushings themselves are worn, the wear is between the
> outer part of bushing (secured to arm) and inner sleeve. AFAIK, the inner
> sleeve(s) is pinched between the frame bits; the arm and outer portion of
> bushing pivot on the stationary sleeve. The bearing surface is bonded (I
> think) rubber + grease though this design aspect may vary.
>
> images of my worn bushing. Bushing attached to arm. Note the slight angle
> of
> sleeve (shows wear):
>
>
> https://lh6.googleusercontent.com/-H7g_E_9VNg4/TaSUCduUCcI/AAAAAAAAEkw/xCrc2
> SIbYYc/s512/UpperCAfebi.jpg
>
> end view of worn bushing. Note how the sleeve is "tilted" up a bit:
>
>
> https://lh5.googleusercontent.com/-fg8c1iI7ulo/TaSUCSFTPcI/AAAAAAAAEk0/TVsiI
> a8ll1Q/s640/UpperCAfebi2.jpg
>
> Those images may negate my theory, but if one had worn bushings, if the
> upper control arm came to rest in a given position before alignment,
> alignment is done, then Vanagon is driven over some large bumps, could the
> arm shift into a different position and render the alignment useless?
>
> A far fetched thought, but I have to wonder.
>
> Neil.
>
> On Mon, Aug 27, 2012 at 9:37 AM, Rocket J Squirrel <
> camping.elliott@gmail.com> wrote:
>
> >
> >
>
>
> > Two years ago my van was in a collision, insurance paid for all the
> > needed work including alignment. Mike's son did the work, I felt that
> > it wasn't steering right so I brought it back a couple weeks later.
> > Mike himself took a look and grumbled that kids are useless, etc., and
> > tweaked everything. No charge.
> >
> > Until they did that work there was a little scrubbing of rubber off
> > the outside edges of the tread, but lately the scrubbing got real bad
> > on the driver's side. In fact, after our 10-day camping trip I saw
> > cord peeking through. Not good.
> >
> > So I've put a pair of my older Coopers on the front and gave the guy a
> > call to make an appointment. He said he was puzzled by the location of
> > the wear. Driver's side outside edge is apparently not a common location.
> >
> > But then, no one can be an expert on all vehicles.
> >
> > Before I see him, does anyone here have any thoughts on what could
> > cause my tire wear?
> >
> > --
> > Jack "Rocket j Squirrel" Elliott
> > 1984 Westfalia, auto trans,
> > Bend, Ore.
> >
>
>
>
> --
> Neil n
>
> 65 kb image Myford Ready For Assembly  http://tinyurl.com/64sx4rp
>
> '88 Slate Blue Westy to be named.
>
> '81 VanaJetta 2.0 "Jaco"  http://tubaneil.googlepages.com/
>
> Vanagon VAG Gas I4/VR Swap Google Group:
>
>
> http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engine
> s
>
>

--
Neil n

65 kb image Myford Ready For Assembly  http://tinyurl.com/64sx4rp

'88 Slate Blue Westy to be named.

'81 VanaJetta 2.0 "Jaco"  http://tubaneil.googlepages.com/

Vanagon VAG Gas I4/VR Swap Google Group:

http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines