Ford 8" and 7 3/4" rears

Just wondering what the differences are and are they compatible to just change the pumpkins? I know the 8" has a filler plug on the pumpkin not the back side of the cover and the 8" looks beafier, thicker mounting housing and more castings on it. Do any 8" rears have the filler pug on the backside cover? Thanks

 

ttt

 

Some 8" carriers have oil fill plugs and some don't. Some 8" housings have fill plugs and some don't. It is possible to assemble an 8" rear end with no practical way to add lubricant.

One modification that I would make is the addition of a drain plug. If you have a drain plug you will be more inclined to service the rear end. Art Morrison sells a weld in 1/2" Flange & Pipe Bung for $10. PN 92851600.

Art Morrison also sells a weld in Rear End Filler Cap & Bung for $34. PN 92851300. Appearance is not quite right for a traditional hot rod but it is a solution if you find yourself with a combination of parts that comes up "Fillerless."

 

They are the same rear. Ford just used a slightly smaller ring gear with some ratios. Everything about them is the same. Where the drain plus is depends on the housing ( year ) and the carrier ( year ) so lot's of combos can come from mixing and matching as bib said.