just traded my 99' 150 SC for an 03' SC , (both 4WD) The rear axle on the 03' is noticebly (sp?) bigger in the pumpkin (2" taller top to bottom), has heavy gussets, and the diff cover looks very similar to a Dana shape....... it's a 3.55 LS, also has 9/16" studs vs. 1/2" on the 99' truck. I was under the impression it should be an 8.8, but it sure doesn't look like one. Did I somehow end up with a better rear axle ?? anyone know what it is ? Thanks, Jim

 

Probably a 9.75". Were both vehicles 4.6 V8s or is the new one a 5.4. 5.4 comes with the 9.75". You can read the tag on the pumpkin and it will tell you the size.