Just found this on Pirate4x4 last week. which does it look like?
![](http://www.pirate4x4.com/forum/attachment.php?attachmentid=159207&stc=1)
![](http://www.pirate4x4.com/forum/attachment.php?attachmentid=159208&stc=1)
A – OEM Toyota Birfield that has been heat treated and cryo’d.
B – OEM Toyota Birfield that has been heat treated, cryo’d and a ring welded around the cup end. There was actually two version of the rings. First there is a .250” dia. ring. Later it was changed to a .188” dia. ring.
C – Aftermarket Birfield (Version 1) that has been heat treated, cryo’d and a 3/16” ring welded around the cup end.
D – Aftermarket Birfield (Version 2) that has been heat treated and cryo’d.
E – 27 Spline Super Longfield. 4340 Cup and Stub, 4340 cage, 300M star & small than OEM balls. I believe that all the parts have also been heat treated and cryo’d. For use with stock type 27 spline inners.
F – 30 Spline Super Longfield. 4340 Cup and Stub, 4340 cage, 300M star & small than OEM balls. I believe that all the parts have also been heat treated and cryo’d. For use with special 30 spline inners.
I’m not saying this is all the variations the Longfield Joints have gone, thru but it’s the general order. (Also I labeled them A-F for discussion sake, so thats something I did for this post and not a standard that Bobby is using.) For instance on both E & F versions oringally had a 4340 star, but during testing it was determined that this material needed to be upgraded to 300M… Also order from A – F does NOT represent Weakest to Strongest. I will explain that later.
http://www.pirate4x4.com/forum/showthread.php?t=305715