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Discussion Starter #41
4 degrees negative castor is absolute minimum on anything I own. Close in on 6 degrees and it starts effecting steering effort noticeably, but you will never have death wobble there.

My Fords are always right around -4 degrees. Never had a castor issue with any of them. My Toyotas start at zero and I take them to -4. Dodges are often around -2 and I take them to -5.
I'm guessing this is a typo and you meant positive (+) castor. I'm pretty sure any amount of negative caster would make for a, well, very interesting, driving experience.

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Discussion Starter #42 (Edited)
Well, it looks like I'm in the wrong line of work. I need to open up an alignment shop where I live because of the four I called this morning, NONE could get me in before Wednesday afternoon.

Business must be GOOD if every alignment shop has a three day wait to get into.

So I said the the heck with it, and ordered some alignment tools off Amazon so I can check/ adjust it myself.

With the castor (and both ways of spelling it are correct, just like grey and gray are both correct) adjustment not really affecting the toe and vice versa (and camber not really being adjustable outside of replacing hard parts), I figured how hard could it be / how bad could I really mess it up.
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Well, it looks like I'm in the wrong line of work. I need to open up an alignment shop where I live because of the four I called this morning, NONE could get me in before Wednesday afternoon.

Business must be GOOD if every alignment shop has a three day wait to get into.

So I said the the heck with it, and ordered some alignment tools of Amazon so I can check/ adjust it myself.

With the castor (and both ways of spelling it are correct, just like grey and gray are both correct) adjustment not really affecting the toe and vice versa (and camber not really being adjustable outside of replacing hard parts), I figured how hard could it be / how bad could I really mess it up.
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tell me about opening up an alignment shop lol, brought the truck in and they toe'd it (badly) and gave it back to me with 1.8 degrees positive castor lmao. I put the kibosh on that right away, the shop manager couldn't understand why i wasn't happy with it and why i wanted to go adjust it myself lol.

castor might get you a little bit of steering wheel off center, but thats it. nothing that will effect tire ware. the factory LCA cams at the axle maxed out gave me a around 5 degrees of castor
 

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Discussion Starter #44
tell me about opening up an alignment shop lol, brought the truck in and they toe'd it (badly) and gave it back to me with 1.8 degrees positive castor lmao. I put the kibosh on that right away, the shop manager couldn't understand why i wasn't happy with it and why i wanted to go adjust it myself lol.

castor might get you a little bit of steering wheel off center, but thats it. nothing that will effect tire ware. the factory LCA cams at the axle maxed out gave me a around 5 degrees of castor
I've got a set of slightly longer aftermarket fixed tubular control arms. They came with the three inch lift kit.

I suppose the aftermarket fixed control arms could also be contributing to a low caster number if they weren't exactly the correct length.
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what sets it off death wobble bump steer, an issue that any suspension with unequal steering arm geometry vs wheel/knuckle articulation faces. straight axles see the most bump steer of any suspension style (IE wheels turning as the suspension cycles from full droop to full compression)

the only parts that ware that can effect castOR are the ball joints or control arms/control arm bushings. see spelling in the wiki article i linked. your castor measurement was not accurate then. no shackles in the front of a second gen truck, try again.

no, but if you repeat things that are true vs old wives tails they eventually permeate the group and you have to stop teaching people the basics
Sorry, I should've been more specific. My comments weren't '94-'98 Dodge specific, but based on experience with vehicles from the Forties through the Seventies, and most recently with a 2006.
But since the principles are the same, I didn't think it mattered.

Anyway, if you trust Wikipedia for information, we're probably much too far apart to have a meaningful discussion.
Now, if you'll excuse me, I'll go and change the spelling of caster in every manual and book I have on the subject.
 

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Sorry, I should've been more specific. My comments weren't '94-'98 Dodge specific, but based on experience with vehicles from the Forties through the Seventies, and most recently with a 2006.
But since the principles are the same, I didn't think it mattered.

Anyway, if you trust Wikipedia for information, we're probably much too far apart to have a meaningful discussion.
Now, if you'll excuse me, I'll go and change the spelling of caster in every manual and book I have on the subject.
believe what you want to believe, but i believe in what produces results. leaf spring straight axle guys that go fast, like 60s gasser and like my gasser 1950 ford with a 52 f1 axle under it usually at a minimum run 5 degrees if not closer to 7 or 9 degrees positive. with leaf spring stuff you've also got to take into account the dynamic castor change as the leaf compresses and flattens out and its net axle rotation. if you dont trust wiki for information, you probably think the internet is a communist plot anyway smh.
 

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I suppose the aftermarket fixed control arms could also be contributing to a low caster number if they weren't exactly the correct length.
they definitely could, but you should still have the factory adjustment at the axle with the eccentric cams on the lower control arm brackets. mine being in the neutral position had my truck at like 1.8 on one side and 2.0 on the other, now with them maxed for the most castor both sides are about 5 degrees
 

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Discussion Starter #48
they definitely could, but you should still have the factory adjustment at the axle with the eccentric cams on the lower control arm brackets. mine being in the neutral position had my truck at like 1.8 on one side and 2.0 on the other, now with them maxed for the most castor both sides are about 5 degrees
Yeah, the eccentric cams are still there (they're part of the axle housing, not part of the control arm).
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Yeah, the eccentric cams are still there (they're part of the axle housing, not part of the control arm).
well i have heard of some people welding the eccentrics in place with adjustable aftermarket control arms (which you really shouldnt do)
 

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My 97 4x4 gets death wobble at seemingly random times. Like I don't necessary have to hit a bump any certain way, sometimes it just seems to starts shaking as I accelerate. Almost everything in the front end has been replaced, the only things that I personally haven't replaced is the steering box itself and the ball joints (both of which seem in good shape, hence the reason I haven't replaced them).

Its got 98-99 HD t-type steering (done with moog parts), a synergy track bar, new moog unit bearings, and a cheap steering stabilizer shock. Its been aligned by a local shop, the steering wheel doesn't pull in any direction, and overall it drives pretty good (when its not wobbling)

I don't have a steering box stabilizer bracket, but I do have a front receiver hitch that bolts between the front frame rails.

Would one of the steering box stabilizer brackets (that are available on everyone's website) be worth the $200-ish they cost? I figure there's a reason that everyone seems to sell them, but that logic doesn't always hold true. Thanks
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Try replacing the front tires with a different brand as that's what it took for me.
 

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All parts are notin good shape. You have failed to change two of the main contributors, steering gear and ball joints. Figure out which of the two or both still have play in them and replace them to solve your problem. Also did you do the track bar? It is the most common source with steering gear being second. Control arms also can contribute. If you have all new/good parts and good alignment you will not have a death wobble problem.
 

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Try replacing the front tires with a different brand as that's what it took for me.
You must be lying. It has been clearly and repeatedly stated above that the tires have nothing to do with it.

Except, maybe, in your case and a couple of mine.
 
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You must be lying. It has been clearly and repeatedly stated above that the tires have nothing to do with it.

Except, maybe, in your case and a couple of mine.
+1 . On my 05 it was the gahy falcon flimsy walled cheapo tires .
 
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Discussion Starter #54
Well, I'm not sure if the tires are a cause or an effect, but there is definitely something odd going on with the front tires that I've never seen before. There are lugs on the front tires that are worn down significantly farther than the lugs around them (see pics below).

How is that even possible for one lug the be worn short , with tall lugs on either side of it??

I run the same tires (albeit in a different size) on another , even heaver, diesel truck with dana 60 front end. And those tires have about 40K miles on them with none of this weirdness (these tires have maybe 15-20K miles). I've had mud tires on at least 5 other solid axle 4x4 trucks of various makes over the years and never seen this before.

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The rear tires still look like new (which they should for only having 15K -ish miles on them)

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Cause ? not sure , besides shocks . What air pressure ?
Steering Geometry is a compromise on a 4x4 truck .

Big rumbly knobbie tires NEED ROTATING on a 4x4 . Come on man get to it . lol.

That tire .. How many sidewall plies ?? It will say right on it .
 

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I ran those tires on my 03 Ford plow truck . Very expensive if i remember correctly .
GREAT if i had the plow on with salt in the bed . WILL ABSOLUTLY kill you in very cold 1" frozen pack snow on the road ,, bare truck. .Reason : large bare blocks with NO siping .
Good in deep snow and good in mud though.
 

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...there is definitely something odd going on with the front tires that I've never seen before. There are lugs on the front tires that are worn down significantly farther than the lugs around them (see pics below).

How is that even possible for one lug the be worn short , with tall lugs on either side of it??
Normally I'd say it's imbalance, but since "it can't be the tires", there must be some other reason.
 

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Discussion Starter #58
Cause ? not sure , besides shocks . What air pressure ?
Steering Geometry is a compromise on a 4x4 truck .

Big rumbly knobbie tires NEED ROTATING on a 4x4 . Come on man get to it . lol.

That tire .. How many sidewall plies ?? It will say right on it .
They're three ply sidewall.

I normally run them at 45 psi.

And I'm rotating them today as soon as I get off work.
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Discussion Starter #59
Normally I'd say it's imbalance, but since "it can't be the tires", there must be some other reason.
I run centramatic tire balancers on this truck. The truck drives surprisingly smooth with them. Going to and from my in-laws house there is a stretch of highway that has a 85mph speed limit ( that's a thing is parts of west Texas). I've ran this truck, keeping up with traffic, at (and maybe even slightly above) that speed limit several times and there's no shake or vibration.

I'm not discounting the balance possibility though as with the centramatics, the tires aren't actually balanced until you get to about 25-35 mph. My other dana 60 diesel truck, with the same tire (different size) , that also has centramatcs, doesn't have this odd tire wear pattern.

Wonder if it has anything to do with the front having the CAD vice lockout hubs (my other dana 60 front end diesel truck that doesn't have the odd wear pattern has lockout hubs)
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I run centramatic tire balancers on this truck...

I'm not discounting the balance possibility though as with the centramatics....
I like Centramatics, and have used them in many applications, but if that tire had a low spot from the factory, a Centramatic may not be able to counteract that.

And I doubt that the CAD has anything to do with it, but lack or rotation does.
 
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