Crabbing???

[float_tested]

I have a 69 F100 2wd. My friend was driving behind me and he said the truck was crabbing a little bit where I was driving straight but he could see the truck have a diagnal slant. Example is seeing the front fender and tire.

Any ideas what this is and how to fix?

[fordman]

alignment of the front end.

[float_tested]

Thanks, just making sure. Does that mean I need to find a place that does cold bending?

If I am going to put new shocks and springs should I wait to get allignment until after?

[fordman]

yes i would wait until you do the other work first. i would make sure they can bend the beams before you go with a certain place.

[papabug71]

Its called "dog-trotting" & these trucks are notorious for it. The reason is, the rear end has a narrower track than the front, meaning the front wheels stick out further than the rear. You can go to a dentside '73+ rear end to eliminate the problem, but its totally a cosmetic issue.

Bottom line is, its normal for these trucks

[70_F100]

[fordman]

i think when he was saying you could see the fender from behind i think the truck was moving sideways down the road. i dont think he meant the wheels looked narrow from the rear.

[papabug71]

Im pretty sure he's talking about the narrow rear end. We'll have to wait untill he replys. You wouldnt believe how many guys tell me my truck has been in a wreck because it "appears" to go down the road sideways

[float_tested]

Hmmmm??? I'm not sure. I was only hearing what my friend was saying. It sounded to me like it had a sideways type movement. Once it is running again I will have to drive behind it and see how bad the problem is.

Thanks for the responses. I was hoping it was going to be running yesterday but am having trouble with carburator.

[papabug71]

Is it pulling to the left or right when you drive? Is it wearing out the front tires? If not, im pretty sure its just the optical illusion due to the rear end having a narrower track than the front.

[ForingaMex]

alignment of the front end.

A front end alignment won't make any difference in this case. If it really is 'Dog-tracking' than the rear end needs to be aligned.

[float_tested]

I didn't notice it pulling one side or the other. I was a bit surprised when he told me. Once it is running again I will pay more attention for any unusual signs. Hopefully it will be up by this weekend.

[papabug71]

How do you line up a leaf sprung rear end?

These trucks track different front vs. rear from the factory. Here's a link to better explain how Ford changed this for 1973. http://fordification.com/tech/chassis-comparison.htm

[fordman]

the only way i can think of a rear end not being aligned properly is worn spring bushings. or the truck has been in a wreck that has bent or push something out of shape. i dont know if broken or sagging springs would have anything to do with the rear end tracking but it could i dont know.

from what i know abou talgining. the front has to be aligned so that it lines up with the rear axle tracking. that is on a 2 wheel alignment. now on 4 wheel alignment they align the wheels so that they line up with the body. so all four wheels will go straight down the road.

now if the truck is out of alignment you may see usual tire wear patterns. on any of the tires.

if the narrow rear end is what he was seeing. he would have seen the front tires. but he probably wouldnt have seen the front fenders. becuase they are on the side of the truck.

i think the only way we are going to find the real answer is to have soemone else drive the truck and have him see what is going on.

[jnewton59]

Around here it was always called running dog legged. From behind the truck looks like it's running sideways or that the body is sitting crooked. I was always told that it is caused by a weak or broken rear spring.