I'm just a bit confused about my truck. I had the right rear axle bearing poop out on me yesterday. Lots of popping sounds from back there. So I decide to tear it all down, head over to NAPA to get my parts. She wants to know which ring gear I have. Dunno, ain't no tag on the punkin' bolts. She says it could be 9.75 or 8.8. So we look at the shape of the punkin' cover and the one I need is for the 9.75 inch r/g. So I figure the bearing should be the one to match the r/g. Not. Turns out the bearing is for the 8.8 r/g. WTH? The truck was built in Canada, Is that just a Canadian thing or what? Did the PO request the bigger ring gear for some reason. Anyways, It's all fixed and good to go now. Was just curious about the differences. Any info would be most welcome.
Oh yeah
98 F150 4x4
5.4 E4od
Off Road and towing pkg.
3.55 non ls

 

This just happened to be a thing with Ford at the time. Nothing's wrong, just the parts used at the time.

9.75 axle uses 8.8 bearings? - F150online Forums

 

Well now I know. Sure was a PITA. Thanks for the reply.