Originally Posted by heyjude076
The wifes 39 Willys came with a 12 bolt Chevy rear. I have no history on it but believe the axles to be stock. One of the 7/16" wheel studs spun when trying to remove the lug nut. I finally got the nut off, removed the drum and the stud in question just pushed out. I miced the knurled end at .465 I also tried to mic the hole in the axle with my dial bore gauge but because of the knurl I could not get a accurate reading. A search for studs returned a range of .472, .475, .480 and .486 knurls. Anyone know how large I can go on the knurl and still press it in. Would you recommend I get a larger knurl and drill the axle to match? I so how much undersize should I drill the axle?
The OEM knurl diameter is 0.472". The amount of clearance that is coming from the worn knurling and how much is from the worn hole in the axle will decide which size knurl you'll be able to use.
In stud applications, for a 7/16" stud, the tolerance for the hole size for the lug is 0.005" to 0.008" less than the knurl
Judging from prior experience and by the looseness of the stud in your axle, I would first try a 0.472" knurl- in case the stud itself took the brunt of the wear.
Depending on that outcome, you could then use a 0.475
" knurl, if the stock 0.472" diameter knurl feels loose.