The driver side wheel studs on my 67 Cutlass have decided they don't want to play well with others and have begun breaking off. I have no idea what size gorilla was used in the past to torque them, but I have slowly downgraded to two studs on that side of the rear axle. I bought replacements from the local parts store but they don't seem to be the right replacement part. The new replacement studs from the parts store have a small shoulder that presumably is supposed to fit in the axle flange but the holes in the axle flange have a different idea about what fits. Standard issue Chevy 12-bolt rear.

Here is a picture of the replacement part. Not the actual one, but a picture lifted from the internet. You can see the base of the stud is slightly larger than the threaded part of the stud. The threaded part is standard 7/16X20.


The studs that have broken off do not have the shoulder at the base, they are pretty much 7/16 from end to end. The parts store has the same part number for 67 Cutlass and a 67 Chevelle (type O, and type C) so what is going on? I know the hole in the axle flange is that tight because when I drove the broken studs out the minor mushrooming of the two hammer hits caused the stud to be a very tight fit to remove. I need studs without any shoulder whatsoever. What am I missing? And where can I find the correct wheel studs? I don't want to drill out the holes in the flange by hand but if I must, I suppose I can.

 

The studs are supposed to be tight and locked in the flange to keep from turning when you tighten the lug nuts. You cannot judge the old with the new as they have been stretched already.

 

I understand how they are supposed to fit. The splined shoulder is designed to "grip" the inside of the hole in the axle flange. The new studs WILL NOT FIT! I have test fit them and the threaded portion of the stud will go through the hole in the flange but the splined portion will not. The shoulder is too large to start into the hole! The shoulder portion of the stud does not "stretch".

 

I’d try looking up wheel studs on auto parts web sites myself to see what is listed, and what the different options may be (if any).

 

Yeah, been doing that and they all show the same thing, a stud with a shoulder larger than the threaded section. Maybe I can pm Monzaz and get some real world info. I know you guys are trying to help but I've covered a lot of ground already.

 

The studs are supposed to be driven in with a press.

 

That is true, but if the studs are the correct size for the hole, they can also be pulled in to the axle flange with the nut and a well lubricated washer. These studs are NOT THE RIGHT SIZE! That is the problem I am running into. I am trying to find out if this is a common problem or if, like everything else about this car, mine is non-standard in some way.

 

Could you post a picture of both side by side? Do your original wheel nuts thread on?

 

Good point; that is another way to do it.

 

Yeah, that's unusual. There are a wide variety of shoulder sizes for wheel studs. Sounds like your axles may be from some other application?

Got pin gauges? Might need to find the true size of the hole in the axle, then find a stud with an appropriate shoulder. Monaz or Brian might have ideas of part numbers to check. I think the Dorman catalog lists the shoulder size?

Sometimes I use Amazon to collect potential part numbers (e.g., search for "7/16 wheel stud") then go to the Rockauto or Dorman catalog to get the specs on each. Did that a couple of times to experiment with heater valves.

OR, measure the studs you have, then drill the axles appropriately.

 

610-186

.472 knurl

 

I have them in stock ALL the times and buy them by the 1000's at a time.

 

Today's lesson in humility it to not test fit a wheel stud from the outside of the axle flange and then tell everyone they are the wrong size. It don't fit that way! I knocked the last broken stud out and measured it and guess what? It was exactly the same size as the replacements I bought! Popped them in from the back side and guess what, they fit! I used a stainless washer and sprayed it with garage door lubricant, threaded the nuts on backwards and tightened the new studs down into the axle flange. Hosed it off with brake cleaner so I wouldn't get any lube on the brakes and all back together. They are just barely long enough to go all the way through the nuts with the aluminum wheels so I think I'll get some a little longer and replace all 10 when I have time. But for now, I have 5 wheel studs on the driver side rear.

 

Glad you got it figured out.