So I have found cracks in my subframe near the steering box. Wanted some opinions on if it could maybe just be welded and put some steel or if it needs to be cut out and replaced by a shop. I ordered a wonderbar for the car as well to prevent this in the future and to hopefully keep it from cracking even more until I get it fixed. Appreciate any thoughts y'all have.
I see nothing there which could not be repaired if done right. Drill a small hole at the termination points of any crack, weld up the cracks. Grind the welds smooth. Next, plate the frame with some steel of the same or greater thickness than the factory material. 14 gauge? 11 gauge? whatever that is. Weld it all up nice, maybe put some holes in the reinforcement plate for plug welds to tie it all in more. Grind it all smooth and paint it dull grey to match.
That's what I would do. Probably not the right way, but it works.
Besides a little welding to fix those rips, you need to find and install a set of crossmember-to-frame rail brackets. There's also a 3rd bracket behind the fender liner that also adds extra support to the steering box.
Your problem was common with the 82-84 Coupes and Berlinettas because these brackets were not used. IIRC beginning an 85 Chevy recognized the problem and added these braces to all Thirdgens. ( The "rod" in the picture below is another added brace that was used from the pass side hood hinge to the firewall lip )
Thanks a ton! I didn’t know there was even more bracing besides the wonder bar. Definitely going to get those asap. Trying to get the cracks welded up this week hopefully. I’m also at some point going to get subframe connectors for the car which will hopefully help as well.
Got the cracks welded up today and its all fixed. The weld aren't winners in the looks department but they'll do for me. No shops wanted to do it so it came down to me and my buddy doing it in his driveway on jack stands and repaying him in a new extension cord. We welded up the cracks just how firebirdwade said and put some flat steel on for some extra support. Much better deal than the one shop trying to charge me $4000 to put a whole new subframe for such an easy fix for someone with lifts but oh well. I also installed the wonderbar and I'm waiting for the brackets that John showed to arrive and then we will be back to good. Really appreciate all the help guys!
Final update on this thread. I got all the brackets on that John showed. Came out great! Need a different bolt for the one so just ignore that lol. Next will be subframe connectors and suspension and get the underneath all good looking. Thanks a bunch guys!
this was common issue on early cars, factory added the bracing later IDK why Wonder bar" was IROC only that and STB added it will drive like a different car- really! its amazing how much load the PS box exerts on suspension.thats what causes the cracking. My 90 Suburban had same issue a buddy came and welded her up and same issue nothing to stop rails from moving.