To try and save some money (and time - so I didn't have to order stuff) for my hi-steer with a king pin D60 I cut up L7 threaded rod to make the studs.
That worked great for over a year, but this weekend I sheared three of the four studs off, and had to remove them on the trail (PITA - drilled them out with the air drill (OBA), then used an easy out to pull them and replaced them. Air drill sucks on graded bolts...)

So I am ordering the dealer only (fine thread on both ends) studs today and am going to swap them in place of the threaded rod.

Question is, are the proper studs a lot stronger than threaded rod? If I use them, is it going to be ok, or shear off again?
I made the arms with the tapered holes on the top, and use tapered nuts just like the stock Chevy steering does.

What do you guys think? Will it be ok then (with the Chevy type steering arm studs), or do I need to get more creative?

Thanks,
Phil Jensen

I have been wondering the same thing. One question, are the stock chev studs' long enough to clear your hi-steer? My hi-steeer arms are 1" thick, and my stock studs only showed 1.25" over teh top of the knuckle.

Anyway...I was chatting with Mike (Part's Mike) the other day about this. I'm running full hydro off my hi-steer arms...Anyway, he suggested drilling a .25" hole through the hi-steer and top of the knuckle (the area with the most material) and inserting some .25" dowel-stock through it. That way you've got a lot of the stresses involved going through the dowel stock first, then the bolts. Sounds good to me...I'm gonna' give it a shot.

Either that will work, or I'm welding the damn things on the knuck's.!

--D

I think drilling two 1/4" holes and inserting rod would be a good idea. One hole in front of the kingpin, one behind. But forget mild steel, get .25" titanium rod!!!

only $17 a foot- http://www.onlinemetals.com/merchant.cfm?pid=4620&step=4&showunits=inches

Can I do that with a drill press and bit, or do I need some kind of machining? 1/4" bit makes bigger than a 1/4" hole, no?

And why only 1/4" - why not 1/2"?

Seems like 1/4" wouldn't make much difference?

As for the titanium, is that the strongest? Stronger than cromoly, or some of the other cold rolled alloys?

I can get just about any type of metal cheap, so what is best?


I will probably do this over the winter - don't want to have to tear down the front end right now during wheeling season. For now I'm just going to get the right GM studs and go with that.

Thanks,
Phil

Originally posted by RockRover
One question, are the stock chev studs' long enough to clear your hi-steer? My hi-steeer arms are 1" thick, and my stock studs only showed 1.25" over teh top of the knuckle.--D

Overall length on the studs that came on my 81 D60 are 2.75" there is more than enough thread to work with my 1" arms.

Phil

If you're going to 'drill' dowel holes, don't bother -- there will be enough slop in the system to allow dynamic forces... <SNAP>

Mill the holes, or bore them, but make them dimensionally perfect, within a few thousandths, and you'll have a stout setup.

Randii

I dont think inserting two dowel pins into the steering knuckle would help much unless the dowels were pressed into the knuckle and the steering arm. If there was any clearance between the parts then they would only do any good if the studs had already failed.

Sounds to me like the nuts holding the steering arm to the knuckle weren't properely torqued. In theory, the studs shouldn't see any shear stress, just axial stress. If the two pieces (the knuckle and the arm) are designed properely, then when the fasteners are torqued down the clamping force will keep the two pieces from moving/sliding via friction. Hope this makes sense. Maybe you could go to larger or more studs (I have never done hi steer on a D60 just a 44 so I don't know if there is even room.)

So if I use the proper studs with the right torque (which is what?) then I shouldn't need dowel pins?

But, if I do the dowel pins, then I should have the knuckle and the arm milled out. Then I can press the pins into the knuckle, and hammer the arm onto the knuckel for a zero tolerance fit?

Thanks,
Phil

seems to me spring steel roll pins are made for just the shear loads you are dealing with.

fyi I use oem studs with a 1.25" thick arm, and tapered nuts and there's plenty of length.

With proper design/torque there are no shear loads.

As harsanyj said, a properly set up connection is a clamping load and the studs only see an axial load.

I'm going to speculate your failed parts failed due to fatigue caused by shear loads.

HTH

r@m

Ok, Roote Moose - how do I make sure it is properly designed?
Holes in the arm are 1/2" and then they were tapered at the top to match the taper on the tapered nuts. I will be using the rediculously expensive stock GM studs soon. Torque them to what?
Anything else need to be done to make it "properly designed"?

Thanks a lot,
Phil Jensen

Originally posted by 1TONTJ
Ok, Roote Moose - how do I make sure it is properly designed?
Holes in the arm are 1/2" and then they were tapered at the top to match the taper on the tapered nuts. I will be using the rediculously expensive stock GM studs soon. Torque them to what?
Anything else need to be done to make it "properly designed"?



What I would do (mainly because I haven't done any engineering work for over 10 years and forget way too much to trust my own calcs) is to replicate how GM does it. Find out what the GM shop manual says about torquing these bolts.

Beyond that, make sure that the holes are as precise as possible as Randii suggested, make sure the arm sits on top of the knuckle completely flat and even (maybe remachine?) and once you've got it reassembled retorque after a weekend or two of use.

These studs are NOT torque to yield right? There is no plastic deformation or strain hardening in the GM bolts in this application?

I really don't like the dowel idea - it adds more stress risers for no good reason.

HTH

r@m

Thanks RM I will do that.

I like your idea better - less work if I don't have to machine the dowel pins for nothing ;)

Plus, I too was worried about weakening it with more holes.

Perhaps my L7 rod only went because it got loose. I will use red locktite on it all when I replace the studs.

Phil
(and I will carry spare studs ;) )

if you want to make holes for pins, drill 1/64 or 1/32" under the size of the pin you want to use, then use a chucking reamer to finish the hole to size. A standard hardened Dowl pin will probably have a higher shear strength than titanium, and will definately be far cheaper. Less Cool, but Far Cheaper. Use the biggest pin that you can fit, within reason and make sure that you get more than one Diameter of depth into the knuckle. Dowl Pins are .0005" over nominal, so if you ream the hole with a standard reamer, you should have a nice tight fit. Use locktite to retain the pin in the knuckle. As far as stress risers go, I dont beleive that there would be too much problem due to the fact that there is already enough stress risers on other parts of the arm. On my av eng arms they bent at the first hole.

Brook :D

The studs from G.M. are NUTS, I just paid a little over 8 bucks a shot for mine:eek:

The nuts that the factory arm use are nothing more than 1/2"x 20 lug nuts. I pulled them and compared the taper to a stock G.M. 7/16 lug nut and a Chrome lug nut from Auto zone in 1/2x20 and the tapers were the same. Got mine from the local parts place. Good american made ones, not the cheezey ones from AutoZone. They are 3/4" on the outside (uses a 3/4 inch socket or wrench vrs the 13/16 that most lug nuts that big use).

Hope this helps.

Depdog

I have to hammer my 1/2 bolts down thru my steering arm thats how tight my holes are...and they dont come loose... I just run regualar bolts no cones

Originally posted by Depdog
The nuts that the factory arm use are nothing more than 1/2"x 20 lug nuts. Hope this helps.

Depdog

I knew that one, discovered the same thing myself. I'm just using Jeep lugnuts for that.

Studs ran me about uS$10 each though!

Phil