This article addresses the different brands available as well as how to
install and weld it properly:

http://www.gowesty.com/library_article.php?id=1144

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>
>  I wonder how many upper control arm bushings are being damaged during spot
>> welding?
>>
>> I've replace the bushings twice and each time I've asked a very highly
>> recommended classic VW shop to do the minimum spot welding as to minimize
>> the amount of heat the rubber and teflon (or whatever) components would be
>> subjected to.  Each time there were several fairly large spot welds, in my
>> opinion, and what appeared to be significant damage to the bushings.  Each
>> time there wasn't much I could do so I installed the bushings, making sure
>> the appropriate shims were in place so excessive pressure was not created
>> by
>> the large mounting bolt.  Each time they were squeaking and clunking after
>> ~5K miles.
>>
>> Do others think the bushings are being destroyed by excessive welding
>> heat?
>>
>> If anyone has had a good experience with control arm bushing replacement,
>> please let us know and indicate how large the welding spots were.  Were
>> special precautions made to reduce the amount and duration of heat in the
>> welding process?  Any other suggestions?
>>
>> What brand of bushings have people had good experiences with?
>>
>> Thanks all,
>>
>> Ed
>>
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