Crab Walking or is it Dog Walking

[Jwawhite]

Wife told me today car doesn't look right traveling down the road. She was in a following car while I was coming back from a body shop.
Apparently it appears the car front end may point towards the left.
I know the frame is fine, car does not pull to one side, but I can tell when the crown in the road affects the steering. There is a bit of play in the wheel and on left turns I do feel some turning resistance.. like a notch probably the steering box. Or .I think this may be from an idling motor/ power steering pump.
Now I did find two body to frame bolts loose, is my car body on the frame a bit sideways? Waiting to install floor insulation before torquing bolts. Is the diffential/ axle out of alignment?
The frame and steering linkage is stock but the power steering pump is with the 302/AOD.
I'm thinking of trying to find a local alignment shop familiar with old cars and ask for a 4 wheel alignment check.
Thoughts?

 

[40cpe]

We called it dog-trot in our neck of the woods. You say your frame is straight, a bent frame could be one cause. Another possibility is the rear axle isn't sitting square with the frame. I would first measure from the axle to a point on the frame that can be identified as the same on both sides, such as a rivet. Then check that the tie bolts in the springs are not broken and are situated in the hole in the spring mount. There could be weird things, such as someone installed unequal length springs. The measurement should tell you if you have a mis-located axle.

 

[Daves55Sedan]

Some possibilities:
If rear leaf springs from two different year cars are used, it is possible that the center pins in the leaf springs (which mate with the spring perches on the rear axle housing) may be in different locations relative to the ends of the springs. That would cause the rear axle housing to be mounted off-perpendicular to the frame side rails. In my neck of the woods, this is known as "dog-tracking" down the road. In extreme cases, it is often impossible to obtain a good front end alignment because the rear wheels are aiming so far off of parallel with respect to the front wheels.
A major corner impact, knocking the frame out of square (re-shaping it into a parallelogram) would have the exact symptoms as described in the mis-matched leaf springs, but it would have had to have been a very bad collision. However, it only takes a couple of degrees to throw square off to the point that a good front end alignment cannot be achieved.
Body to frame mounting may be off somewhat, but you should be able to tell by noticing problems with hood misalignment and the two front air deflector panels on each side of the radiator are both slid as far as they can be in one direction in attempt to keep centered with the radiator support.

 

[KULTULZ]

I'm thinking of trying to find a local alignment shop familiar with old cars and ask for a 4 wheel alignment check.

Thoughts?

What you need (IMO) is a THRUST ANGLE ALIGNMENT where the rear axle is determined to be square with the frame and the front end is adjusted from that determination.

A four wheel alignment is for a car that has an adjustable rear suspension assembly.

If the rear end axle is determined to be out-of-align/square, you then go about determining the cause(es) by tramming the frame. Modern frame equipment can do this with sound or infra-red systems easily if specs for a 56 FORD is included in the software.

The 57 FORD SHOP MANUAL has the frame measurement charts. I do not know if the 56 does.


Have you noticed any irregular tire wear?

 

[bobss396]

We called it crabbing. In extreme cases you can see quite a bit of one side of the car body and not the other. The best thing is to do the follow-me test and look at the rear and front tires only. Most likely with the old cars the centering pin on the spring perch is badly worn or loose.

 

[Ole Don]

Stock 55 rear axles are mounted in a rubber sandwich. The spring center bolt fits in a hole in the sandwich up in to the axle pad. If your rubber has deteriorated, and someone just tightened up the U bolt nuts, there is a very good chance the rear axle is not square with the car. If you have a good floor jack and stands, it is easy to check. If heavy work on your back is not your cup of tea, find a young guy who will listen and understand what you are explaining.

 

[Jwawhite]

Thanks guys, think I'll start out with measuring axle to frame and measure length of springs. Just a look over all appears ok.

Not sure where my axle/differential came from, it's a cut down 8" Spicer/ Dana

I'd also like to check back wheels to front but don't have a long enough straightedge. T square at rear wheel and string to front wheel?

 

[Daves55Sedan]

If the rear end axle is determined to be out-of-align/square, you then go about determining the cause(es) by tramming the frame. Modern frame equipment can do this with sound or infra-red systems easily if specs for a 56 FORD is included in the software.

Most cars nowadays are unibody aren't they? SUV's? Pickup trucks? So who would have actual frame straightening equipment suitable for dealing with these heavy structural steel frames? Diesel truck repair facilities (18 wheelers)? And would they want to bother with this stuff? Would it require removing body off frame prior to delivering to a place that agreed to do the work?

 

[Daves55Sedan]

My guess is, that if a 54/55/56 Ford car frame had been in a collision bad enough to parallelogram the frame, it would almost certainly mean that the front frame crossmember welds to the siderails would need to be ground off prior to any frame correction, and that the frame siderails around the giant steel pipe crossmember under the engine would need to be heated up red hot on both sides all during the frame correction process. Some of the other crossmember connections to the siderails are relatively fluid and might tweek fairly easily if they are only riveted, but all connections should be inspected for factory welds which may need to be ground off to permit correction. I would be very skeptical that any body/frame specialist would take these things into consideration. If you find that you do need frame work, you should be ready to point out frame construction peculiarities to the service man prior to an agreement to re-square the frame.

 

[KULTULZ]

Most cars nowadays are unibody aren't they? SUV's? Pickup trucks? So who would have actual frame straightening equipment suitable for dealing with these heavy structural steel frames? Diesel truck repair facilities (18 wheelers)? And would they want to bother with this stuff? Would it require removing body off frame prior to delivering to a place that agreed to do the work?

Any modern well equipped shop will have one as it is required to be competitive in the industry. Tying down and pulling is basically the same with either full frame or uni-body. A well equipped system (with optional equipment) (w/ trained and experienced tech) can do most anything.

Pickups and SUV's (according to model) are full frame.

And of course you will come across a frame that has been tweaked too far and calls for replacement.


Would a shop wish to touch it? Depends on how busy they are. Remember, you are paying labor by the hour. Most large metros have specialty shops that specialize in this type of work.

 

[KULTULZ]

Thanks guys, think I'll start out with measuring axle to frame and measure length of springs. Just a look over all appears ok.

Not sure where my axle/differential came from, it's a cut down 8" Spicer/ Dana

I'd also like to check back wheels to front but don't have a long enough straightedge. T square at rear wheel and string to front wheel?

IMO-


You would be better served to find a quality alignment shop (not WallyWorld) and have a THRUST ANGLE alignment performed. The results if not satisfactory will direct you where to start looking for the problem.

On a solid rear axle vehicle, this requires a thrust angle alignment that allows the technician to confirm that all four wheels are "square" with each other. Thrust angle alignments also identify vehicles that would "dog track" going down the road with the rear end offset from the front. If the thrust angle isn't zero on many solid rear axle vehicles, a trip to a frame straightening shop is required to return the rear axle to its original location.

SOURCE- https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=4

OLD TECH TRAM BAR-

- https://www.autobodytoolmart.com/ch...MIrsm1_8vz2wIV1LfACh094gQBEAQYASABEgLoyfD_BwE

Renumber the stress crack @ the left door latch pillar? It may be a symptom.

 

[deuce5wndw]

Measure your track width front and rear. Maybe the rear is narrower and it isn't really dog walking. Just appears to be.

 

[KULTULZ]

Not sure where my axle/differential came from, it's a cut down 8" Spicer/ Dana

When you say, cut-down? Could it be a later 8.8"? Photo of rear end and suspension?

We never did figure out what the drive-line came out of, did we?

If the rear was from a coil spring car, hopefully the spring mounts were put on the housing correctly...

 

[super flat]

Just take a tape measure and measure front hub to rear hub and see if it matches first.

 

[dmsfrr]

Just take a tape measure and measure front hub to rear hub and see if it matches first.

That can work, daughter got a used awd SUV that looked crooked going down the road. I checked it w/ a tape measure. The passenger side measured a bit over 1/2 inch more than the drivers side. A four wheel alignment fixed it.

If a non-original axle under the car was a DIY thing chances are good it wasn't mounted correctly.
.

 

[tinman080]

I did frame repair for 45 years. From a Pull-Dozer to a Power Post and finished up on a Chief EZ-Liner. The first thing that should be looked at before the first scratch is looked at is the frame and ALL attached parts. The frame should be checked for square, mash and sag. I've seen many, many FULL FRAME-TYPE vehicles dog-track due to an accident. Virtually all of them had one or more of the following(1.) a bent front lower control arm (2.) A bent rear end housing (3.) A frame that is diamonded ( the entire frame rail shifted to the rear on one side or the other. no longer square) (4.) A deep sag or mash at the cowl area resulting in a front wheel being back somewhat on one side or the other. (5.) A frame rail still pushed towards the center as the result of a side hit.The average shop generally has one or two guys that are competent to diagnose and repair drivability problems. Sometimes they have none. Most younger guys don't have a clue how to diagnose, set up and repair a full-frame car. They just haven't been exposed to them. Anything built before about 1972 will have a rather limber frame, which will move around a lot dimensionally when hit. A post- 1949 Ford is a little better than a Model A, but not too much. I'm NOT running down your car, it's an observation of later design vs earlier design. Call your local adjuster at your insurance company CLAIMS office or center. They can refer you to a claims estimator. He can refer you to a competent shop who can assist you. Make certain he understands that the repair results will in no way be his responsibility in ANY way.Don't rely on a friend or aquaintance to find a good frame shop. The average customer thinks the car is great if it is delivered with a nice shine. All advice given from a auto body repairman's perspective. Best of luck!

 

[tinman080]

Another quick observation....all manufacturers have a + or - rail length allowance on their frame charts. Usually it is 3-5 mm, about a 1/4''. The dead-on factory spec is 125''.Say the left frame rail is 125 1/4'' long and the right rail is 124 3/4'' long. Both are in specs, yet the car is 1/2'' different from side to side. What do you do? That's where a good frame man and alignment guy can make a shop managers life easy. lol

 

[Jwawhite]

Lots of great info thanks.

K, will work up some photos soon. The axle housings I think was cut at the housing to fit the undercarriage of the car, new axles may have been installed. I was able to track down the work order and will also attach it soon.

There is a peculiarity of this car, the front end is wider than the rear, at least the body is.

There is an old, long established, frame shop in town that I'll take the car to late August.

 

[Jwawhite]

Here' some photos, a look over things seem fine, rubber bushings are there, correct number of leaf springs and what's wrong with rear brake Line?

 

[dmsfrr]

The axle may have been narrowed for wider wheels to fit under the fenders or because it was from a wider/larger car (I'm not familiar with different axle types).

In photo #4 that looks like a low-pressure compression fitting, the same type used to hook up the water line to the ice maker in your kitchen fridge, not for brake lines.
The image is a bit fuzzy, hope I'm wrong.
.