Will my ride be fine if I weld up the front subframe/crossmember instead of bolting it in? I've got bent studs in the rails so my friend suggested he would weld in the new crossmember. What are the negative effects of doing this?

 

welding is weaker than bolting. Think of how thick the studs are....now thick of the tickness of the penetration of a weld. Which one's thicker?

I wouldn't recommend it at all.

I would find another stud (cut it off a junk car by cutting a huge section of frame rail out) and weld that it.

 

Anyone happen to know the thread / length? I could just get a grade X (8.5..10?) bolts and fender washers and drop new ones in.

 

I could swear that I just replied to this topic, but my post doesn't exist? Meh, whatever...

The crossmember is about 3/16" thick, and the sheet metal you would be welding it to is about 2MM at the most. Welding will not be sufficient as the thin metal will crack near the welds when stress is applied. If you look at the stock setup, the bolt actually goes totally through the frame rail and is welded at the stop. Lots of strength.

My vote would be to drill the old stud out, then weld in a new stud following the factory weld lines. Get a skilled welder to do this because it will be tricky to get full penetration on the stud without burning the sheet metal.

 

^ agreed.... not recommended for hard driving!