Steering All Over the Place at 55mph+

[72bluNblu]

Just wanted to note that the steering linkage (idler, pitman arm, centerlink, gear box) are different on 73+.

If he has a ‘67 K it’s irrelevant, since the ‘73+ center link won’t work with the ‘67 idler, and the ‘73 up idler won’t fit the K.

If it’s a 68+ K, it could be either steering set up and it doesn’t matter, both work fine. And if he somehow has a large sector pitman on a small sector steering box, well, it would be unsteerable at any speed.

And FYI, the manual boxes never changed. Same for the whole run for A/B/E bodies.

 

[Oldmanmopar]

As stated . Look to see how the idler is fastened to the K-member. If it has a through bolt with a nut instead of just a nut on top . It would be a later K-member. The first picture is of the later style with the bolt slipped down through. The next 2 are of the later style bracket being installed

 

[RustyRatRod]

It's easy to visually spot a 67 bayonet style idler. Only one tab coming off the K.
The 68 and newer use double shear mounting with a top and bottom plate coming off the K member.

With the A-body migrating from economy car in 1960 to a bigger sometimes performance car, they made things right. (Too bad they didn't go to the Big Bolt Pattern in 67)

Maybe @mosleyme will be kind enough to help you out. He's in Plano.

I'm not trying to start an argument, just asking a question. What about the early A bodies? They only have one idler arm tab too. If it was such a bad thing, wouldn't we be seeing lots of failures? I've never seen even one. What about the 67 is different or worse than the early cars?

 

[Oldmanmopar]

I'm not trying to start an argument, just asking a question. What about the early A bodies? They only have one idler arm tab too. If it was such a bad thing, wouldn't we be seeing lots of failures? I've never seen even one. What about the 67 is different or worse than the early cars?

Well they upgraded them in 68 for a reason. It wasn't to save money. They were just a weak link in the steering that they themselves discovered. I remember when all the old cars were like that and as soon as you got that shake it was time for an idler arm. Its not they break constantly but they do have a problem of getting loose and if they fail your screwed. So why take the chance . If there was a replacement k-member for the early A's . The owners would be replacing them.

 

[67Mungo]

A lot of good info so far, but I can add a little.
When I first got my Dart it would darn near change lanes if I hit one of those reflectors in the road, and the feel of the car overall was exactly like you described.
Scary huh?

My problems were caused by badly worn lower control arm bushings.
Once I replaced those and aligned it with more caster it smoothed right out and got WAY more stable.
I commonly run 80-90 on the more open freeways now with total confidence.

Some already mentioned steering and suspension parts, but since I went through the exact same thing you described, I thought I would tell you.

Very Scary Indeed! I think I'll take it for an alignment first, especially with that positive caster, and have the mechanic (one I trust who works on classics) inspect what everyone on the forum is discussing. I wish I had more pics to share but I'll post some before and afters of what I replaced. The upper control arm bushings looked and felt good but didn't inspect the bottom. As a novice mechanic I was worried about the force from the torsion bar which I didn't relive pressure (once again a novice trying to get the job done and was proud of myself for even being able to do ball joints and tie rod ends ). The boots on the Pitman and Idler arms were shot so probably a project for the summer anyway. At the time it took me a few hours to get that upper ball joint out and was ready to get it back together. I'll try to post more pics this weekend and get that alignment scheduled ASAP. Once again, y'all have been fantastic and thankful for the forum!

 

[67Dart273]

I'm not trying to start an argument, just asking a question. What about the early A bodies? They only have one idler arm tab too. If it was such a bad thing, wouldn't we be seeing lots of failures? I've never seen even one. What about the 67 is different or worse than the early cars?

The one in my 67 was VERY VERY bad, but the present issue is that they are hard to get (one year) and VERY expensive

 

[Kern Dog]

The offset upper control arm bushings are Moog K7103. You can order them at an auto parts store, through Rock Auto or maybe even Summit Racing.

 

[KosmicKuda]

I'm not trying to start an argument, just asking a question. What about the early A bodies? They only have one idler arm tab too. If it was such a bad thing, wouldn't we be seeing lots of failures? I've never seen even one. What about the 67 is different or worse than the early cars?

Yeah, don't forget these cars were designed in the late 50's. When introduced in 1960, the Valiant had 13 X 4-1/2" wheels rolling on 6.50 X 13" tires. (165 X 13) That design carried right through the 60's. For instance, the spare tire well fits that tire nicely with a flat floor above the fiber board. E-70 tires in 68. Oops the tire sticks up above the floor but we're not going to retool the well.

I give Chrysler credit for upgrading starting in 1968 model year. (67 stud mount) Look at any GM car of the same era. What do you see? Single shear and probably worn. Grab a tire at 3 and 9:00 and move side-to-side. Looser than a $2 *****.

I also have a 64 Valiant with the cantilevered idler arm. (195/70 on 14" Rallyes) I've contemplated converting to a solid double shear with a little fab work.

 

[KosmicKuda]

The key is when you get your new alignment, insist on getting as much positive caster as the tech can get. With stock components that may only be 1-1.5 degrees but that'll make a huge difference. Do not have them go by the factory specs. With good solid parts, you'll have a good driver!

You might be able to eyeball the thin LCA bushings. If you see ANY visible cracking, don't go any further before replacing.

Another thing, don't final tighten the fasteners until the weight of the car is on the tires. I put the tires on ramps or big chunks of wood.

My own personal experience is the 64 Valiant drives very well with radials. I drive 320 miles to Carlisle each way and it's great.

The 68 cuda tracks like a freight train with the upper offset Moog bushings. (Only 1.75*) I can take my hands off the wheel at any speed and both are completely stable.

 

[Mattax]

The one in my 67 was VERY VERY bad, but the present issue is that they are hard to get (one year) and VERY expensive

Exactly. This is the one problem. When they do wear they are a one year only part.
I went through about 3 in the many years I autocrossed (with sticky tires) using the '67 K-frame in my '67.
I know people who autocross with the earlier cars too, and plenty of people rallied those early cars. So I agree its a weaker design but no more of hazzard than any other part in the steering.

THE PROBLEM... since I've had it I've basically kept it under 55mph. I did notice if I do a sudden lane change it feels like I'm going to lose control. If you wobble the steering a wheel roughly a 1/4" either way it's pretty non-responsive.

Approach it this way.
1. Is it related to the alignment? Toe out will cause a darting response. Get a shop manual. The front suspension chapter explanations are excellent. The procedure for setting alignment remains the same. Hieght, Camber, Caster, recheck camber, Toe. All four must be done, done in that order and done at ride height. The specs can be adjusted as mentioned earlier as high crowned roads and bias ply tires are no longer in play (for the most part).

2. Is something loose?
The play in the steering wheel is within the norms, although it shouldn't really be noticable while driving.

The first thing to check is the wheel bearings. Normally I'd say check the front, but as the car is new to you, check the rear axle play as well.
- check the front wheel bearing play by holding the tire at 12 and 6 o'clock.
Next check for steering play. have someone turn the steering wheel while you observe under the hood. Then jack one wheel at a time up in the air and work the week while watching the linkage. Do not go underneath without a jackstand! You're just looking for any connection that shows looseness. Then do the other side. Observe each portion of the linkage, tire rod ends, idler, pitman, to see if they all move perfectly together and no up down play either.

Then do the ball joint and control arm checks as the shop manual explains.

Can this be from the wider front wheelbase?

All RWD Chryslers have wider front wheel track than rear.

 

[Demonx2]

My $0.02.....I know EXACTLY how you feel. You are describing my avatar car but mine gets bad at speeds above 70+ mph (partway to the 1/8 mile mark). Mine's not fixed yet but I know it is due to having NO positive caster. Lucky to get it to 0deg caster. Feels exactly as you describe - car wants to swerve and swap ends.

Before it goes back to the track, new SPA fully adjustable UCA's I got from Peter Bergman go in. You can bet it will have at least +2deg of caster to start with. I suspect your alignment likely does not have any or at least has insufficient positive caster. These guys on here made me a believer and my car's antics backed them up!! I encourage you to follow these guy's advice!

 

[72bluNblu]

My $0.02.....I know EXACTLY how you feel. You are describing my avatar car but mine gets bad at speeds above 70+ mph (partway to the 1/8 mile mark). Mine's not fixed yet but I know it is due to having NO positive caster. Lucky to get it to 0deg caster. Feels exactly as you describe - car wants to swerve and swap ends.

Before it goes back to the track, new SPA fully adjustable UCA's I got from Peter Bergman go in. You can bet it will have at least +2deg of caster to start with. I suspect your alignment likely does not have any or at least has insufficient positive caster. These guys on here made me a believer and my car's antics backed them up!! I encourage you to follow these guy's advice!

You wont have any trouble getting +2° or a lot more with the SPC UCA’s, I have +6.5° with mine. A drag race set up is a bit different than what I run, but yeah, even a couple of degrees will make a big difference.

It’s hard to overstate that the original alignment specs were intended for bias ply tires and are completely backwards for radials. The tire construction totally changes how the tires act under loads, and radials need positive caster. With little positive caster, or even no or negative caster, radials will feel like driving a shopping cart.

Unfortunately, the stock parts weren’t really designed for a significant amount of positive caster. The offset bushings definitely can fix that if used to increase caster, typically that will get you a good +3.5° which is good for most drivers and tire set ups. As the front tires get wider, more positive caster helps keep the wide tires from tracking. Which is why I run so much, I’ve got 275/35/18’s up front. So a “pro-touring” or handling set up with wide front tires can use a lot more than what you can get with just offset bushings.

 

[Kern Dog]

Caster goes negative as the suspension rises. A car 2" higher than stock in front will surely be at zero or negative caster.
A car with a rake....where the rear is much higher than the front will also have very little if any caster.
The upper ball joint needs to be rearward more than the lower ball joint to have caster. The higher the rear of the car, the less caster will occur.
The worst is a car that is jacked up in the rear and the front.

 

[Demonx2]

72bluNblu and Kern Dog - you guys must have seen the avatar car!! It does sit higher in the rear (CalTracs w/split monos) and the front has M/T #1573 26" tall front tires. Top of the tire is even with the fender opening.

This is an old school throwback car - one I always wanted in the 70's but didn't have the means to make. So I built this one like I would have then and here we are. You can see it really lifts and stands up front and rear heading down the track. Those SPC arms will go on in the next 6 weeks before it goes back to the track.

Not meaning to hijack the thread - just wanting to share with @67Mungo that you guys are spot on. "Gotta get some caster!!"

 

[sccachallenger]

Check the toe.

Absolutely the first thing I would do!
Sounds like a car with 1/4" of toe OUT.
You can verify this with a tape measure yourself.
You'll figure it out

 

[YY1]

I have always run my cars higher than stock in the rear and usually a bit lower than stock in the front.

Never had issues with steering unless the alignment needed adjusted or had worn part(s).

Also, raising the rear up to 3 inches and lowering the front an inch never seemed to mess with steering/alignment unless it was right on the edge of being out before.

 

[Kern Dog]

This is an old school throwback car - one I always wanted in the 70's but didn't have the means to make. So I built this one like I would have then and here we are. You can see it really lifts and stands up front and rear heading down the track. Those SPC arms will go on in the next 6 weeks before it goes back to the track.




Not meaning to hijack the thread - just wanting to share with @67Mungo that you guys are spot on. "Gotta get some caster!!"

This is a beautiful car.
If the car sits like this at rest, you surely have no caster at this point unless you have aftermarket parts in the front end. These cars don't have much caster to begin with. Look at this chart that I posted elsewhere:

At just about 5/8" over a stock ride height, this car they mapped went into NEGative caster and it got worse the higher the front end went. The caster goes POSitive as the suspension compresses/lowers.

 

[Demonx2]

View attachment 1716076731

This is a beautiful car.
If the car sits like this at rest, you surely have no caster at this point unless you have aftermarket parts in the front end. These cars don't have much caster to begin with. Look at this chart that I posted elsewhere:

View attachment 1716076733

At just about 5/8" over a stock ride height, this car they mapped went into NEGative caster and it got worse the higher the front end went. The caster goes POSitive as the suspension compresses/lowers.

Thx! No, the pic is of the car probably about 60ft out. Rear axle separates a bunch (4+ inches from appearance) and the front lifts a bunch too (gets a tad of air under the LF tire and RF barely touching). Guessing from pics the front lifts about 3". So I'll be setting the caster such that it remains positive at these elevated positions. Obviously after the acceleration is reduced further down track, the front end should settle a bit and help the situation. I'll try various settings to get it right! Thx for that chart!

 

[67Mungo]

UPDATE
I think y'all are on to it with caster. I found a shop in Dallas that works on classics to do an alignment and am am in the process of scheduling an appointment . But decided this afternoon to take a look for myself. The cam nut andjustment assembly is not even close to allowing for positive caster and eyeballing the ball joints it looks like I have negative caster. Before I jacked it up took an angle finder to it and have 2 Deg neg camber as well. I wonder I'm scared to drive it!

Attached are pics.

As far as the k member and 1967 idler arm discussion it looks like a post 67 idler arm which I assume means the k member was swapped along the way. I know it's irrelevant but thought since y'all have been participating in this thread you'd want to know.

After I have alignment results I'll let you know how off and more importantly how she handles when proper.

 

[72bluNblu]

Ok, well that is definitely a '68-72 K frame and not a '67, so that's good. I guess I should say it's '68+, since we can't see the engine mounts but the idler and steering link are '68-72.

And you're right, your cam bolts are definitely not set for maximum caster. If you don't have offset bushings even maximum + caster won't be a ton, so, I would set max caster and then see where the camber ends up and try to keep as much + caster as possible.

You can do this yourself if you want, changing the caster and camber slightly shouldn't have a huge effect on toe. This is especially true in your case, since your current settings are basically right down the middle and the changes will offset each other. Loosen up the cam bolts, and to set maximum caster you want the front arm of the UCA all the way "out", so the head of the bolt should be as far away from the inner fender as possible. The rear arm of the UCA should be all the way "in", so, the head of the bolt all the way in toward the inner fender. That will push the upper ball joint backward, maximizing positive caster. Like this...

Now, if you don't have any alignment gear you will definitely still want to take it to an alignment shop that deals in classics. But if you set the caster as I described, and then eyeball the camber you should be ok. Camber becomes visible at about 1°, so, at the point you notice the tops of the tires are tilted slightly in toward the car you should have about -1°. If your car currently has -2° of camber it should be quite obvious that the tops of the tires are tilted in toward the car. For most normal street driving you only want about -.25° to about -.5° camber, which basically looks like the tires are straight up and down. At least to me, I have my own alignment gear and based on doing some eyeball alignments the point where I notice stuff being tilted is pretty close to 1°.

At any rate, if you set max caster and the camber doesn't look too crazy you should be able to drive it to the alignment shop and see where it's at. As long as it's not a really long drive any minor change in toe shouldn't be enough to completely scrub the tires. Ride height changes affect the toe more than the camber bolts, and being almost right down the middle now helps your cause in the toe-in department.

 

[BillGrissom]

Sounds like you have excessive play in the steering, which is very dangerous. Check toe-in with a tape measure. Easy to do if your tires have straight channels, and a helper to hold the tape measure. You want 1/8" toe-in for RWD, or 1/16" if all parts are new and tight. The fronts rotate back slightly when driving (depending on steering linkage play). You want the fronts exactly parallel when driving. Any toe-out will cause the car to wander on the highway. As the suspension sags over time, the fronts get toe-out, which is likely why people say old cars wander. Can also check by holding a straight-edge along each front tire and sight at the rear, if same track width front-back. Sight should hit ~1" off the rear, so need a helper holding a ruler (1" inward for FWD, which is easier). Only use an alignment shop you trust. Many who worked at one say some techs just nudge the laser sensors until they get a green printout, without adjusting anything on the car.

I agree with going for the most caster you can. Set fwd cam adjuster as far out as possible and aft cam inward. That moves the upper ball-joint as far aft as possible. You want the line thru upper and lower to project to the road in front of the tire contact patch as possible (for shopping-cart effect). The reason radial tires don't work as well is that they are stiffer in driving direction so doesn't deflect that patch as far backwards as with bias-ply. I used Moog offset bushings (don't follow their instructions which are for a pushed-in top mount after a collision). Another issue is where the lower ball-joint sits. You want them as far forward as possible, for more caster. That is affected by the strut rods to the lower radiator support. If the rubber bushings are degraded, or the support bent aft (or weld repair), or the front nut backed off, that could let the ball-joint move aft. I have seen aftermarket adjustable strut rods. There are also aftermarket adjustable tubular upper control arms. Best are the Moog improved strut rod bushings (2-part disks you don't have to squish thru the hole).

You can't also adjust camber, but will probably wind up fine, with the tires slightly leaning in at top (negative camber). Radial tires can deflect in that direction better to accommodate more camber. Factory spec was leaning out slightly, which is strange today since tuners go extreme on neg camber, some even using rounded motorcycle-like tires to match. Rick Ehrenberg of Mopar Action wrote about suggested alignment specs, which you can find here in a search. I think toe-in is most critical for smooth handling, at least after "no play".

 

[92b]

If you have a fairly flat floor to work on you can use a framing square against the tire to measure camber. If you are at approximately zero camber the square will cntact the top of the tire and the bottom at the same time. If the square contacts the bottom and there is a gap at the top you have negitive camber. I would measure your current camber and record it. Also mark you cam bolt positions with a paint stick or sharpie before you start moving them.

 

[Dave_J]

I had put in a complete front PST kit tor the 1965 A body in my 65 Barracuda but had to change a few things as the prior owner converted the front to Road Runner 4 piston disc's and LBP.

After all was done at slow speeds it was stellar to drive but get up to 65 MPH and it was all wonky.

• First issue I found was the steering shaft joint was missing one side slider. Fixed that but did not help.
• Second issue found was the Idler arm and pitman arms were worn, replaced but did not help.
• While yanking on the pitman arm to remove it, the manual steering box would move on its bolts. The bolts were tight. ??? I remover the steering box and found the nuts that were welded in the K-member were not welded any more.

I remover the K-member, bead blasted it, ground out the areas for the nuts, put the steering box in snug and tack welded new nuts in. Then removed the steering box and fully welded the nuts in. I then did Freiburgers "Flying Brick" K-member mods by adding more bent to shape steel and added gussits all over.

 

[Dave_J]

More....

When done, I added the Steer & Gear's Cop Car power box and upgraded the tie rod tubes to the larger B body one. The Barrracuda now felt like it had a Power Rack and Pinion.

 

[MILO]

Make sure there is no slop,play in your steering box