Volaredon you descibed my situation to a tee and yes you can feel it at the wheel, useing moog parts and would never consider cornner auto parts store stuff for this. Had shaft balance checked several years ago when I did the b&t and rear u-joint and have one of the rare ones that had the weights still intact. Part of the problem is no shops around here can even align this thing to my satisfaction. Maybe if i could get a decent alignment things would change the pinnion bearing on the other hand could be the culprit..Dave

Charlie,

This is just a hunch, but I'm suspecting the L/U Torque converters might be developing some some of wear-induced out of balance condition. Just like your Dippy, some days it's worse than others... go figure. One might think if the TC were the problem, it would be different each time it locks up. Maybe that's not it, but I've just about ruled everything else out in the truck. Maybe the 904 is so overtaxed in a "big" car/truck application that it causes some kind of abnormal wear to develop. The Fifth Ave used to carry it's own weight across country twice a year, and I don't think it was ever overhauled before I owned it. I've never torn either of the two down, so I don't know. The truck shake developed about a year after I got it. I always said it caught it from the 5th Ave !

"DW"

GT63, find a nice flat piece of concrete and break out a floor jack, tape measure, plumb bob and some 3/4" sockets. I gave up on the morons at the average alignment shop ages ago.

"DW"

Dagnabbit, forgot to log in!

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If it ain't broke, fix it!

DW Sounds like a future article to me . Will have to share my secrect formula for setting torsion bar to correct ride height in exchange. Uses the same items you mention above but the trick is how and where you measure.. Dave

I like to set ride height to taste. Gotta get that where you want it, of course, before proceding.

There are four basic adjustable realms on a stock chrysler torsion bar front end.

1. Ride Height, with which you're already familiar.

2. Toe, for this you need chalk and a tape measure (or a toe gauge, if you wish).

3. Camber, this is where the plumb bob comes into play. This is whether the tire leans in or out at the top, or is straight up and down. I like mine set at 0 deg., but there are factory specs and road racing specs. I'd bet Lou would be an authority on that.

4. Caster, I have read ways of dialing in this setting in the driveway, but I prefer "ball park" and a test drive. I like as much caster as I can get away with. This affects steering effort and tracking, and will make your car pull to the side with the least caster if they are not equal. Note that caster and camber are directly related, and it takes some skill to manipulate one without throwing off the other.

There is really one more thing, and that is centering the steering box/wheel. When's the last time you saw the idiot down at the local quik lube get this right? It's really more important than just cosmetics, a straight ahead steering wheel is the point of tightest mesh on the steering sector.

"DW"

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If it ain't broke, fix it!

Thanks DW did some reading last night and studied my vintage Chilton books. Trying to find a article that I have where a person made a alignment rack using scrap lumber/jack stands and pvc pipe as a toe gauge and used a 4x8 plywood sheet on which the vehicle was parked with all measurements inscribe to properly do the settings..(note: vehicle was fully supported by jack stands)....Dave

Yeah, everything has to be set at "ride height", or it will be off. I usually jack the vehicle up to unload the upper control arms when adjusting camber/caster, then I let it down and move the car back and forth a few feet to let the wheels find their track and then I bounce the front end up and down several times on each side to let it find "home". Yes, this can be very labor intensive and meticulous work, but all my vehicles drive straight ahead, don't pull, don't put unusual wear on the tires and handle pretty good for what they are. Those high-tech alignment racks are great, but when you man it with a low-tech highschool drop-out with no understanding of how any of these settings affect handling, what good is it?

"DW"

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If it ain't broke, fix it!

Well I guess ill weigh in on this. My dart has a vibration. Has always had since I put tires on it. They are balanced perfectly. They are not however round. No tire is perfectly round and some are egg shaped worse than others. Spin them on a balancer and watch them. Maybe your problem or maybe not.

As per the alignment suggestions of dennis I am very impressed with his understanding of alignment angles and intrigued by his do it yourself alignments but I am not sure I understand how you measure caster dennis? I dont mean to question you but I am very interested in this.
Also 0 degress camber doesnt wear tires for you?? I have been a tech in many garages and i did about a year as an alignment only tech. In that year I noticed that anything set with the wheel set at 0 seemed to cup the tires. I theorized this was because the tire was taking a direct beating when hitting bumps and unable to transfer energy as efficientlty to the suspension parts. But it is a theory that I have found no support for in any technical writings.
Do you have any trouble with tires cupping dennis?
Sorry to ask questions on someones post but im very curious.

Nope, I don't cup tires. O deg is usually in the range of the factory specs for older Chrysler cars, I have found. In the past, on decent handling cars like my old Road Runner, I'd give it just a smidgen of negative camber. Difficult to express in degrees when using the plumb bob method, but just a hair in at the top of the tire.

As I said, I like to adjust the max amount of positive caster that I can get away with and still get the camber I want. Then I have to equalize R and L sides, and I do this by repeated test drives. I know there are other ways, this is my way, and it really doesn't matter to me what the angle ends up being, as long as I get in as much as possible. I find that this really enhances tracking and directional stability (they say you can have too much, resulting in bump steer or wander, but I have never had this problem... Also, as the positive caster is increased, so is steering effort, this can be a concern on heavy manual steer cars).

I'll take my el cheapo line-ups to a big-money alignment shop rookie rip-off any day . Not saying there aren't professionals out there... Just hard to find them.

"DW"

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If it ain't broke, fix it!

That is really cool. with a bare minimum amount of equipment you have figured out for yourself what I cannot teach some of the guys I have worked with no matter how hard I try. Even with 20 grand worth of equipment . Maybe I'm just a crappy teacer.

Yes excessive positive caster will cause problems like high speed unstability. But I have never had an old mopar that I could dial in that much positive caster. I currently have my swinger set at -.5 camber and + 3.5 caster with the ride height in the weeds. Handles better than ever.

For the one that said that a 0 deg. reading would cup out the tires, it isn't the alignment setting that cups tires. Bad front end parts, dead shocks, and lack of rotation cause cupping, or imbalance for those unlucky enuf to be riding on bias tires. ) degress camber means that the sidewall of the tire is basically at exactly a 90 deg. angle to the road. A pos. camber reading means that the tire is leaning out at the top compared to the bottom, and a negative camber reading says that the tops are leaning in. Camber is set on a rack with a car not rolling down the road, the idea is to shoot for 0 deg. camber while driving, things DO change from what the machine says when centrifugal force and such comes in. As far as pulls, etc, you need to keep the left and right camber and caster close side to side if you want the car to go straight. What happens when you get a shopping cart with a stuck wheel? It Pulls, right? That is what an excessive left/right difference does to your alignment. Ever notice, on motorcycles, the front wheel is out AHEAD of you, and when a "chopper" is built, that front wheel is even further in front? These bikes hold the road pretty well, huh? If you drew a line straight vertical thru the front frame tube that the forks go on, then measure the angle of the forks from that vertical, that is your CASTER angle. On bikes, it will always be a positive since the wheel is ahead of the forks. If the center axle of the front wheel was BEHIND that vertical tube, it would be NEGATIVE. How many bikes do you see built that way? Not many! With a Neg. caster reading, it would be a real job to keep that bike up at speed, right? Think of a CASTER on a shopping cart. The wheel follows behind the place that the caster mounts to the frame. This, again, is neg. caster. Notice how the wheels flutter back-n-forth? Imagine too much neg. caster on your car. Now think again of how well that motorcycle holds the road with the wheel out front of the fork mount centerline. They handle pretty good, huh? On the subject of tire wear relating to alignment, if you run your hand across the tread and you catch like a sharp edge, it is usually toe wear. Camber, and toe, too, can cause either the inside or outside edge to wear faster than the rest. Wear on BOTH edges of the same tire, though, is most often from air pressure being constantly low. These will all be smooth, if it is cupped/scalloped, it is most likely lack of rotation. (Yes, I know that they rotate while driving down the road, but you need to unbolt them and swap the fronts and backs around about every other oil change)I wish that you guys were closer to Illinois, Most of the time at the job, I do alignments and front end repairs. I'd love the chance to show you that some of us really CAN do a good alignment! I am ASE Master Certified! There is a little more to it than this, but it should give you the idea.

Nice dissertation on steering geometry, volaredon... What about steering axis inclination and Ackerman angle, huh??

Seriously, there ARE people in the business who know what they are doing, but they are few and far between anymore. Mostly it's about scoring a quick buck and selling people a bunch of BS. That is just my personal cynical attitude, and a lot of it comes from where I live, I think. You've got people nowadays that know what button to push, but they have no clue as to WHY, and most of them couldn't care less.

"DW"

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If it ain't broke, fix it!

Don thank you for the brief explanation of dterering angles. That sums it up in a much more articulate manner than I can. I am well aware of the causes of tire wear. My theory of 0 degree camber wears tires is probably baseless. It is just one of those things that seemed like a pattern. I am sure you are well aware of pattern failures and such in this business.
But unfortunately I think dennis has a good point. I,like yourself, take a lot of pride in doing a quality job and constantly look for ways to improve. Unfortunately that isnt the case in most shops. In this area at least. On a regular basis I fix screw ups from other shops 2 of them are shops whos primary business is alignment alignment with ase certified techs.
It is sickening to see the stuff come in with an off center wheel or a pull. the story is usually the same. Either worn out front end parts or the toe is all that was set. Pathetic. this gives us all a bad name. Not only was the customer not given a quality service but the shop lost a huge potential for profit.Not only by not fixing what was needed but now because the customer is no longer going back there in most cases.
To bad there is not a better way than ase's to certify a tech. Just because they pass a test,which they can buy prep tests for,and meet the experience requirement doesnt mean they know or care to do the job right.This irritates me to the point that I let my ase certs expire. They will not get a nickel from me for even a recert test until the system is fixed. Prep tests are bull sh--. I am sure this irritates you and all of us who try to do our job well so Ill get off my soapbox.

My hat goes off to both of you guys (guest, volaredon) for your knowledge and pride you take in your work. I think I was pretty clear that no offense was meant to guys like yourselves, it is a shame that you seem to be a dying breed. People don't want to take the time for the most part to discover WHY something "is" in this fast paced society. Just rush rush rush, get the next one in and turn a dollar. I can't remember as a kid how many times I was told that my steering wheel simply "couldn't be centered", "that's just how they come out sometimes" after plunking down a hard earned 30 bucks or so. "And that tire that looks like it's laying over? That's spec, that's where the machine said put it..." And I've honestly been told that I had "worn front end parts" after doing a complete rebuild!

This is not just true of front end alignments, it's true of all vocations. I have close ties in the automotive repair industry, and like was said, I hear and see horror stories daily, and some poor unsuspecting fool is always getting the short end of someone else's incompetence or utter disregard to worksmanship or propriety. Talk about a soapbox! I'll get off mine, now!

"DW"

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If it ain't broke, fix it!