How to repair crack in subframe? Pictures included

[Helmsy]

Fixing or replacing is fine but it would be nice to know what actually caused it to eliminate it happening again.

[PorscheGAL]

I agree. Since I am replacing all the bushings in the front, I have a pretty good view from the bottom. I am not finding any damage elsewhere. This is also the first time I have had it up on my new lift so I am not able to say when it happened. I couldn't say whether it was before I bought it (2009) or after.

[fredmeister]

Originally Posted by PorscheGAL

Folks

I found a crack on the crossmember subframe where the torsion bar retaining cap rest. Obviously, it will need to be welded, but how? Does the subframe need to come off or can it be welded in place?

I don't know how this could happen. I'm in the middle of a suspension refresh and found this problem.


Side view


bottom view

There is another crack in the top picture in the web of the piece that concerns me more. Problem with a crack, especially in an aluminum part that is susceptible to fatigue failure, is that once it is cracked it fails quickly.
You have to realize that the load from the torsion bar is reacted at the steel insert in the upper corner of the crossmember so you dont want it cracking in that area.
If it were me, I would go with the replacement piece and avoid using the welded piece.

fred

[930cabman]

I would never trust a welded suspension part. Aluminum is a funny metal, especially when welding. Alot of heat is generated and the grain structure will be altered. I am sure many of these exist in the parts yards.

Good luck