what size bolts for backing plates?

[74fldart]

hi fellas, im putting the backing plates on my rear end and since i dont have the factory bolts i was wondering what size do you guys use. this is for a 8/3/4 / dana set up. i tried to get a 3/8 bolt in the holes but the axle tube is so close to the hole in the bearing housing that the head of the bolt wont allow it to go in right, i guess the factory ones were ground down on the one side or flattened off. anyway i tried a 5/16 and it will work but the holes look like there made for a 3/8. moser sells a set but its like $ 30 .00 . any body have any suggesations?

 

[RedFish]

3/8 dia. bolts with special / undersized heads would explain the high cost

 

[mrtires24]

My diffs had studs, with nuts.

 

[grumpuscreature]

They aren't bolts, they are serrated shank studs with round heads that have a flat on one side. Have one in my hand now.