Looking at rear leafs on Rockauto. Can someone help explain the differences in stamping?

DORMAN Part # 929301 {#4886185AB, 4886187AB, 52000545AB}
Rear; Heavy Duty Suspension; Stamped LJ
Rear; Heavy Duty Suspension; Stamped LL
Rear; Heavy Duty Suspension; Stamped LS
Rear; Heavy Duty Suspension; Stamped LK

 

The L* could be some type of factory code, why don't you give RA a call to find out?

 

I will, I just wanted to talk to my friends here first...

 

LL - 3-1/8" free arch, load rating 405
LM - 5-5/8" free arch, load rating 605
LS - 6" free arch, load rating 675
LT - 7" free arch, load rating 755

from here:
http://www.naxja.org/forum/showthread.php?t=1089753