The workshop manual refers to the two metal parts bolted inline to the chassis as a subframe.  Mine are corroded but I have read elsewhere that they can be removed and discarded, no need to renew.  Is this correct ?

2004 foresterX

Cheers Jim

They added to get crash safety rating for europe market.
can remove it but sharp mot inspector may comment and you could have insurance issues in a more serious accident claim .
You can pick up the front frames in solid shape for peanuts off of eBay or marketplace so proper repair not expensive.
some of the fixing bolts can be a right struggle though ...
If the front frame rough I would do good in depth evaluation of rear frame and body structure and all suspension arms to get good idea on vehicle state then choose what want do based on evaluated condition .

Thanks again Mr B , I will talk to my MOT tester for an opinion and will get back to you.

I removed the corroded subframe and my car recently passed the MOT test.  I hope this is of help to others. 

Cheers Jim