I'm not sure of the parts name but the front brace that goes under the transmission and the oil pan has a bolt that will not go in or out. both sides have two small bolts and one big bolt. the left side big bolt won't go in or out and one of the small ones continuously spins. I think the threads are stripped

 

If it wontgo in or out, the nut it is attached to (inside the unibody?) has broken off its welds. You can cut off the bolt, but how you'd go about replacing it I'm not sure. I don't have my car near to check but usually in a case like this you need to cut a window to access the other end of that bolt, so you can install a new nut. Careful where you cut :/

 

Wow man what a hell

 

So the nut inside of the crossmember broke off and is stuck on the bolt. I was still able to drive the bolt into the body partially leaving about 1 cm of the bolt sticking out of the transverse member. I'm going to ride it like this for now until I get either a weld job or a new cross member.

 

wasn’t expecting either that or the Spanish Inquisition

cut the bolt head off and then drill the hole out with a 22mm drill bit, bevel the hole some, insert this in flush, and TIG weld it in

https://www.mcmaster.com/90374A115/

they have other sizes, but am pretty sure it’s M10x1.25

they sell a high strength version in M10x1.5 makes a great exhaust manifold flange nut too.
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