Drop beam handling

[61flareside]

Ok so you guys have to help me here... Ive been driving my truck for a week now, just finished 4.6 swap, I have drop beam with the drop downs for the center link from Sid. The springs are alittle too soft now, but my big issue is control. It is almost uncontrollable even just cruising. This is my first beam truck, but I've installed and built several ifs front ends but on this one I wanted to keep the beam as kind of a older hot rod style thing. So I need some feed back from you guys running the beam. Because right now I can't even take this on the freeway it feels like its gunna kill me. It feels a lot like bad bump steer but I cycled the front end and its damn near none, also was wondering if maybe the centerlink was flexing so much that it feels like bump steer. Appreciate any feed back on this.

Jesse

[graybeard]

How much caster? Radials or bias for the look?

[jamesdfo]

Jesse; Is your steering box still in the originla location, or have you raised it to compensate for everything elses orientation changing?
I ask because I seem to recall mention of this modification (raising steering box) either here on slick60s, or on the HAMB.....

James

[61flareside]

I put in 4degree shims for caster which is was what sid told me to use. And I'm using radials.

About the steering box, no I didn't raise it. I read about that when I was looking into the beam but I guess I took from it that you don't Need to do that with a dropped beam. Like I said this is my first beamed truck so you tell me... Thanks for the help.

[jamesdfo]

Jesse: I haven't done it, so I'm only reiterating what I have read previously.
Best to wait for someone who is running a dropped straight axle to weigh in, as real world experience trumps reading about it EVERY TIME:)

James

[Rusty 63]

Our '63 danced all over the road whenever we hit a bump with two steering stabilizers on it. I always thought that was just how straight axles rode... and why i'm stalled in the midst of a cv swap…

[graybeard]

Straight axles don't have to ride like that. Something is really wrong, it is not just inherent to the design. Guys go over 200 MPH ever year at Bonneville, in straight axle cars. Truckers run up and down our highways every minute of every hour of every day on straight axle front suspension systems. My '32 pickup has a 2" dropped axle under it, buggy sprung & staight arrow. We've got a 2001 F650 dump truck straight axle( not dropped ) never has swapped lanes, doesn't wander a bit.
It's easy to blame something you've heard bad mouthed all your life, simple blows a lot of guy's skirts up. Get that truck in a good experienced front end shop, they'll get you straightned out, the first thing I would want checked would be total caster.

[Uncle Skip]

If you have the axle put in correctly (there is a right and left side) it has got to be the caster. Call Sid and tell him whats going on. If anybody can help you its him.
My straight axle truck tracks straight as an arrow, hands off at 80.
Toe in, the only other adjustable feature on the axle would only result in extreme tire wear.
Granted, some of that may be due to the front sway bar, but incorrect caster is what I suspect is causing your problem.

[jamesdfo]

Jesse: Here is one of the threads I saw regarding raising the steering box (starting on pg 3)

viewtopic.php?f=32&t=19250

[61flareside]

Ok well I can tell you that the spring bushings are pretty beat so ill change those. I agree that these beams should go good cant argue there. I'm fairly certain I asked Sid about the beam ad he said their is no left or right... Just saying. What about centerlink? An old time racer told me they used to weld angle iron on to them because when they would brake, the dang things would bend like crazy with the weigh on them.

[Indy63]

Rule number 1 to keep in mind with the way a vehicle drives and asking for advice: Everyone has their own opinion of what is acceptable.

Put an angle finder on the kingpin and find what your caster actually is. You should have 4-8 degrees (pointed toward the rear) caster to help prevent wandering. Also measure toe in/ out - put a chalk mark on each front tire and measure front and back from the same chalk marks - you want 1/16-1/8" toe in at the tread (you'll probably need a helper). You need to replace worn bushings, shocks, tie rod ends, etc. if you have not already. Any suspension/ steering system will be sloppy with worn-out parts. The stock tie rod is pretty wimpy as you have noticed. An easy solution to that would be to sleeve it externally with appropriate sized tubing.

Also, you do have bump steer if you did not move the box or bend the steering arm. To put it simply, with a dropped axle and stock steering, you change the angle of the drag link in relation to the spring. This difference in angle in addition to the drag link being considerably shorter than the back half of the spring results in a good deal of bump steer - some find this to be acceptable or ignore it, others can't stand it (bumpsteer is also present from the factory, but the new drag link angle compounds the issue). Limited suspension travel can keep it down some, but it is still there. To "fix" it, you either have to raise the box or lower the axle side of the drag link by heating and bending the steering arm the same amount the axles is dropped. 'Z'ed drag links do nothing to fix the problem, nor do steering stabilizers as they do not fix the geometrical problem - they only mask it at best.

[Drapal]

This is Sid. Are you sure you have your caster shims in right? The thick part of the shim goes to the back of the truck. I've had many guys put them in wrong and they drive just like your talking about. A straight axle will go down the road nice and straight if its set right. Semi trucks drive more miles a year then any vehicle and its a straight axle. The other thing to try is jump up and down on the bumper. If the steering wheel goes side to side like crazy it's a bump steer issue. The draglink should be level to the frame between the pitman arm and left steering arm. If it is not the left steering arm need to be bent down. If you need to give me a call I'm always glad to help.

[61flareside]

Thanks for replys. Appreciate all the input from everyone. I will have to check the drag link angle tomorrow, not sure about where it's at. I did jump on it and cycle it before to check for bump steer and I THOUGHT it was good but I will check that as well tomorrow. Just to be clear I have no complaints about the product sid, I have no doubt that this issue is a result of something I messed up, just trying to figure out what it was...

Jesse

[Drapal]

If your steering wheel don't move side to side when jumping up and down on the bumper. Then check your tow in. Make sure you have at least 1/8" tow in. Jesse Thanks again for your business. You are always welcome to call me and I'll do my best to help you.

[61flareside]

Little update... So talked to Sid, very helpful. He gave me some things to try. Toe in made a huge difference. I had it set at zero. Adjusted it to an 1/8 in and that helped it alot. Also told me how to bend the steering arm which i will probably do next chance I get. It drives much better now, but it still fights you a bit over bumps. May give it a little more toe to see if that solves it totally before I bend steering arm.

[Paul Merrell]

I know on my truck I had problems with handling and I had check the front and could not find any problems. So I checked the rear axle, found that the leaf spring bushings was worn out. And the mount bolt hole was egg shaped. Repaired all of that and the truck did not dance around anymore.