Technical Wheel studs

It's my first time changing wheel studs .The rear end is a 12 bolt chevy and the stock studs came out easy about 5-6 hits with a hammer.
I looked at a few you tube videos and it looked simple enough.
I am using a Snao-on 1/2" impact gun @ 120 psi.
The knurled part can be pulled about 1/16" then nothing
I got the new studs from Summit, they are 12"-20 X 3" with the knurled part is .562.
The stock studs are .519.
Seams like a big difference.

Fred

 

I had the same problem, ruined a moser axle trying to make them fit......buy the right studs

 

drill the holes., something around .550 would be nice.

 

But how big WERE they? .519 is after you pulled them out, so they are now smaller.

 

What is the inside diameter of the holes in the axles? As "gas pumper" stated you may need to enlarge the hole.
Pressing the studs into the axle is a lot better than trying to draw them in with an impact,and I know we have all done it before,but that does not make it right ! (Just saying)

 

Those ".562's" will never go into the where the ".519's" once were. Sorry, but it sounds like you got the wrong studs. A lot easier to go back and get the right studs.

 

I have changed numerous sets of hubs to wheel studs from wheel bolts and found that about .015 or so interference fit worked well for me. BUT, I have always pulled the axle shafts and hubs are used a shop press for removal and installation.

In the first place, those 4, 5 or 6 hammer blows per stud (20 to 30 per hub/flange) to remove them is battering the front wheel bearings and is not good for the "C" clips and axles in the rear end.

Further, even with the proper interference fit, by drawing in the new studs with a nut and impact wrench, you are running the risk of damaging the threads and quite possibly the stud itself. It is also difficult to fully/properly seat the stud in the hub or axle flange by that method.

I really, really recommend you get either the correct diameter studs to fit the existing hole or drill the hub/flange for the proper interference fit AND MOST OF ALL, use a shop press for installation and with simple, but important, fixtures to support the hubs and flanges while doing so.

 

interferance fit is usually .005 max but not .050 , and we press them in , when we were in a bind we would freeze them on a block of dry ice for 5 minutes or the house freezer for 30 minutes then pull them in with a stud puller or a nut and 2 greased up washers and a spacer so the nut won't bind on the part that s not threaded that sticks thru that locates the drum or rotor , never redrill your axle ends unless you have a mill or drill press with a rotary table to hold the axle otherwise a little off center on one hole and you will have balance problems or rim fitting issues . but being .050 out your only going to break stuff , get the proper size units

 

Stimpy,

'Re the interference fit.....wouldn't it be the case that on smooth surface interference fit the dimension difference would be only a few thousandths, as you suggest, but given the serrated shank, a bit greater difference would be desired?

My reasoning is that the difference in the minor and major diameters of the serration not only allows for, but requires, a greater interference for the serrations to adequately "bite" into the axle/hub stud.

In any case, we agree on the desirability of using a press to install them.

 

As stated, PRESS ONLY! It's not just your life at risk, it's others!

 

Did you have a larger spacer on the bottom so the serrations could come thru the flange?

 

The hole is .500.
The studs from Summit are .549 .565 .589 and up to .685.
The .549 looks to be to big since the one I took out is .519.

 

Are you just looking at Summit brand studs? If you call Summit, I'm sure they have studs by Moser, ARP, etc. that will have a smaller knurl, and press in easier.

 

a) Yes, they're the wrong studs. .040 interference may well crack the stud hole in your hub if you actually managed to get it in there. Stop now. Drill the holes (ARP, Moroso, etc. have the required interference fit spec in the specs on their website) or get different studs. If you've been wailing on the studs with the air-gun cranked up I'd be concerned they might already be overtorqued.

b) As for stud removal - whether you can get a stud out with a hammer is dependent on age and how it was put together. Some will come out readily, some are rusted in place or too tight to budge. Wheel bearings, retainers, etc. have to be able to take a lot of abuse in use so use of REASONABLE force is not going to damage the bearing, etc - and if you use UNREASONABLE force I think you're more likely to bend/crack the hub flange (especially true of cast front drum hubs). Soak well with ATF/acetone and wait a few minutes. There are C-clamp-style stud pullers available if you can't get the part off the car to a press, much better than tearing up the hub.

 

I bought 20 studs ( sum-910106) from Summit ,this is before I knew to measure the knurl part. I need to call them to see what will work.

 

Press fits for wheel studs are something around a 1/64" interference. For a stud that measures .625 over the knurl, use a 39/64" drill. Realistically anything close will retain the stud, even as low as a .007 interference should be fine.

Bob