Greetings,
The subframe tabs to which the lower control arms of some, older, Mercedes, sports cars are bolted had a tendency to crack. So Mercedes recalled some of these cars -- particularly those with iron blocks -- to allow dealers to weld 1/4" thick, steel gussets between the tabs and the subframe's steell cross-member, thereby reinforcing the tabs.
Unfortunately, Mercedes refused to recognize that the same cars with lighter, aluminum blocks also had a tendency to crack. So people with these cars have essentially been left to fend for themselves -- which is why I am posting this message.
More specifically, Mercedes recommends using a MIG welder to weld these gussets between the tabs and subframe's cross-member. However, a very experienced welder I know sees no reason why he can't do the job with the ARC welder he's been using on car frames and other things for the last 30 years.
My question is "Is there any reason why an arc welder can't or shouldn't be used to weld these gussets to my car's subframe?" The only factor I can think of is that the arc welder may have a greater tendency to burn the rubber bushings that surround the bolts passing through the tabs. OTOH, I have read that there are heat resistant materials that can be used to shield such things from the heat generated during welding?
I would therefore appreciate any advice anyone can give me on the best way to go here. Thanks very much in advance.
Tom