Front Axle 1939 Ford pickup

[Fech]

Hello all,
Does anyone have a diagram or picture of a 1939 pickup front axel with dimensions from various reference points? My father's pickup has an issue when turning the steering wheel to the right. The front left wheel doesn’t rotate, it drags instead, leaving rubber marks on the floor.

[ActionYobbo]

Pickup uses car parts so you can use 4 door info

[petehoovie]

Originally Posted by Fech

Hello all,
Does anyone have a diagram or picture of a 1939 pickup front axel with dimensions from various reference points? My father's pickup has an issue when turning the steering wheel to the right. The front left wheel doesn’t rotate, it drags instead, leaving rubber marks on the floor.

[Ggmac]

Can you take pics of the wheels, steering linkage and complete front end . It could be a few things . What is leading you to the axle ? Does it look bent ?

[Fech]

Thank you for your quick response!
The axel was bent, so years back it was sent to be "straightened". Now, when testing the pickup, we noticed the marks on the floor because the left wheel was dragging, and it also looked inclined.
https://youtu.be/Qngk83g8684?si=v0C7yaFy4BFKbaGP

[Mart]

Sponsored Links (Register now to hide all advertisements)

Ok. I have watched the video and would say your ackermann is screwed up. One or both steering arms might have been bent. With the wheels in the straight ahead position you ought to be able to project a line from the kingpin to the centre of the back axle. (diff).
The steering arm tie rod end should lie on this line.
Some things look a little strange in the pics, for example that type of spring is normally used on later cars and where it fits in the crossmember is not stock 39 style. That in itself wouldn't cause your problem but it was just something I noticed.

Mart.

[Fech]

Thank you Mart for the explanation!

I will try the suggested layout tomorrow.

Should I ignore that the issue is related to the front axle? Because it was sent to be straightened. I don't have experience, and I am not sure how to check if the repair was done correctly.

[Randy in ca]

As Mart suggested, I would check the steering arms on the spindle to see if one or both are apt to be bent. Basically this can have the potential to mess up the toe-in difference between the wheels that should be there while turning. A quick check can be made by comparing the distances from the backing plate to the end of the arm on each side.

Have you checked the toe-in while the wheels are pointed ahead?

[Mart]

As long as the axle looks straight to the eye it will be ok. A slight error in straightness will not cause the problem you are describing.
One question, though, are the wheels aligned correctly when in the straight ahead position? Around 1/8" toe in is about right.

[Fech]

Thank you guys for the help!
One quick question: does the front axle have a side when installing it? Apparently, it fits both ways, because the axle doesn't have any marks for reference.

[pistonbroke]

Thinking geometrically after seeing the video it would appear your steering arms do not match . I would take a measurement from the lower center of the kingpin the the center of the tie rod stud and also from a common point on the backing plate to the stud as well on both sides. I think you will find your problem. Extreme error in caster could cause this but would be very unusual. Tim

[flatford8]

This is the Ackerman angle top view......Mark

[petehoovie]

Originally Posted by flatford8

This is the Ackerman angle top view......Mark

[Fech]

I apologize for my ignorance. Please clarify which backing plate are you referring to?
Also, please see the attached pictures of the rods. Apparently they are bent, but I am not sure if they are factory bent, or I have to straighten them.

[flatford8]

Don’t apologize......there is a big difference in not knowing and being ignorant. The backing plate is the round plate in your last pic that the brake shoes attach to. Use that as a reference to take your measurements. I think all the pieces should be straight. Check the Ackerman angle from the pic I posted.....Mark

[Mart]

The tubular link is the tie rod and that should be straight. The mainly solid one is the drag link and is normally not straight.

[Bob C]

Not familiar with V8 axles and it may be the picture but this one does
not appear to be straight.

[petehoovie]

Originally Posted by Bob C

Not familiar with V8 axles and it may be the picture but this one does
not appear to be straight.

[Randy in ca]

Here's a couple of pictures to show how the toe settings should be on turning.

The angles shown shouldn't vary much for vehicles with a near normal wheelbase

-


-

[pistonbroke]

To my way of thinking, if the axle was on backwards the problem would be the same turning either way not just right. Therefor its something else. Have you checked to see if the camber is the same? This is a simple check done on a level floor with two jack stands of the same height in the same spot on the left and right side of the axle. I like to use the perch bolt for this but all the maters is that they are in matching positions right and left with the tires off the floor. You can now check your camber by putting a level vertically on the outside of the tire between the six and twelve clock positions. To be more accurate you can use a good know to be straight rim with no tire. The level should show the same reading on both sides. And as said above, don't apologize , just learn . That's why we all come together here. Cheers, Tim