11.5" cases and spiders came in two different sizes, with large and small hub sizes on the side gears. Small hub diameter is 1.816" and came in '07 & down GM differentials. Large hub diameter is 2.060" and came in '08 & up GM differentials and all Dodge differentials. This spider gear kit is a large hub design.

This Part Fits:

Year	Make	Model	Submodel
2003,2005-2010	Dodge	Ram 2500	Laramie
2006-2010	Dodge	Ram 2500	Power Wagon
2003-2010	Dodge	Ram 2500	SLT
2006-2007	Dodge	Ram 2500	Sport
2003-2010	Dodge	Ram 2500	ST
2008-2010	Dodge	Ram 2500	SXT
2010	Dodge	Ram 2500	TRX
2006-2007	Dodge	Ram 2500	TRX4
2003	Dodge	Ram 2500 Van	Base
2003-2010	Dodge	Ram 3500	Laramie
2003-2010	Dodge	Ram 3500	SLT
2006-2007	Dodge	Ram 3500	Sport
2003-2010	Dodge	Ram 3500	ST
2008-2010	Dodge	Ram 3500	SXT
2007	Dodge	Ram 3500	TRX4
2011	Ram	3500	SLT