My rear end snaped right in one of the arms. I had my buddy welded back with a strong thick weld. Do you guys think it will hold? Or am I wasting my time? I really don't want to buy a new one.

 

SNAPED!

 

It is aluminum. Did your buddy weld it together properly? The size of the weld does not matter as much as doing it CORRECTLY does. If he used regular 'ol welding and not specifically an aluminum welder using a tri-mix of gas I don't see it holding together well.

 

 

potter potter potter potter

 

rear control arm snapped??? what did you do?

snape snape severus snape, DUMBLEDORE!

 

oh shnap!

 

Not a rear control arm. I don't know what they are called but one of the arms that hold the rear end.
I was launching the car and the rear just snaped, I'm pretty sure he welded it good as he does it for a living. I guess I'll have to just try it and cross fingers?I would just hate to be left out on the side of the road

 

i'd start looking for a new one. Should be fairly cheap at a scrap yard

 

Yesh if only someone was selling a rear end...

 

It will be fine if welded properly. I've seen many diffs like that last for a very long time once welded. Welded ones are usually stronger as the diff is designed to break there in a rear end accident. (Diff is knotched to allow this to break)

 

anyone with the notched model diff should grind the notch to be a smooth transition over like 2 inches and it wont break so easily.

 

Sounds like it might be a good idea to reinforce this area before trying extremely hard launches.

Good bit of info, Thanks

 

This didn't manage to find its way to parts group did it?

 

It just so happens I have spare in my garage. Whats it worth to you?

 

Been there done that.

 

I'm going to give this one a try and see what happens, I'll let you know if it doesn't hold up.

 

Dumb question:

So once the notch is removed, it won't break as easily although it's now thinner throughout the 2" length?

 

yup. the notch is a designed-in stress concentration.

it focuses the stress at a single point on the surface instead of distributing it along a longer length naturally.

same deal for cutting glass... you score a line to create a stress concentration and it breaks easily at the line. it is weaker at that point than even a thinner piece of glass.

 

So why did Mazda put the notch in anyway? Prevent frame damage in rear end collision?