Shimmy shakin' dana 60 front

[Scrub]

I have an 86 k30 with duals. It had a utility box on it which was heavy. I took that off and put a pretty light flat bed on it.
Today I hooked up a trailer that had a pretty heavy drawbar weight.
Net result, the front end is lighter than ever. About five times today, the front end would go into a shimmy spaz attack that made me have to stop the truck.
I drove this home from Phoenix to Oregon and it never did that before.
I jacked it up and the bushing are tight as hell, zero play. I have a little play in the steering box, but I am not sure how to tighten it up as I know you can break a steering box easy if you go too far.
The stabilizer seems to have some air in it or something. It will be tight as heck, then get sloppy and then tight again. I need a recomendation on a new one. My parts guy ordered me a Rancho, but the Ranchos he had (didn't fit) where just about the same as mine, Tight, loose then tight again.

NAPA has a Monroe stabilizer instock.

Which is the best? also, how to tighten that box

Thanks in advance

[TX_Mudder]

Don't adjust the steering box worm gear (the screw you are referring to on the top.) You are asking for trouble. If you are convinced the steering box is worn out (IMO not likely) then replace it with a rebuilt one for about 150 - 200. More likely is that the slack in your steering is a combination of things, esp. the steering shaft which no one ever replaces.

I don't tow a lot so I don't know this for sure, but maybe your tongue weight is too much? WOuldn't that cause the front end to be unloaded and wouldmake a shimmy happen? Again I don't tow much, obviously less than you, so I don't know for sure.

Obviously make sure the tie rod ends and drag link ends are good.

As far as a steering stabilizer goes, I would say you'd probably eb happy running a dual stabilizer like this one
http://www.4wheelparts.com/product2....HHG6MTDPJXFWVF

The other thing to check is the condition of your kingpins. For the upper, the nylon bushing is something that wears out on occasion and is very easy to replace. On the lower, the bearing, if worn, can cause excessive play. You can get a complete kit from parts mike
http://www.partsmikeparts.com/dana_6...ebuilt_kit.htm

Everything except for the kinpin itself, the black tapered metal piece in the upper right hand corner under the nylon bushing, is very easy to replace.

-- Mike

[Mike C]

If the truck doesn't do it without the trailer, most likely that is where the trouble is. First thing I would do is install a load distribtion hitch to put weight back on the front tires.

[charlieo]

We had a 67 4x4 and the steering box bolts were backed out quite a ways causing a real bad shimmy . Check those bolts for tightness too !

[Scrub]

Thanks for all the replies.
I replaced the stabilizer with a new Rancho that was a lot bigger and every thing seems fine. I went and got my cow squeeze. I hit the scales on the way home. I weighed 16,350 with just a little over a ton of tongue weight. Drove like a dream. I purposely build my trailers with the axle to the back and try to pull them with the hitch tucked up as close to the rear axle as possible. You do get a lot of toungue weight that way, but it also never sways much, and on a 2wd, you can get more traction.

As far as the weight distribution hitch, I know they are a good product, but this is a truck damn-it :-) Something about them reminds me of my Grandpa pulling his 32 foot RV trailer with the Family station wagon. For my regular pickup, I think it wold be fine.

I talked to a bunch of people and they all said that if you need to adjust the box, it is usually shot. Everything else is as tight as a nut. Dana 60 fronts with duals just like to shimmy. I got to thinking about it and my 2000 Ford started doing it at 20k miles after I took the camper off. I let air pressure down and that helped.

[stlaser]

Does scrub realize most hitches are built for MAXIMUM 600LBS tongue weight? Axles have a purpose, its to carry a load. I build a parts for a major hitch manufacturer in northern Indiana. Trust me the hitches are designed to take twice the load of recomended weight before they fail but personally I wouldn't push it. If a trailer is loaded properly they don't sway. I load and pull them daily. Just a thought to chew on, good luck.

[stlaser]

Oh and a trailer must be built properly. Thus axles not toward rear, read any trailer building book or better yet ask a proficient engineer.

[Scrub]

I respect that both statements are true for the average person. I'm not the average person.

The axles on my truck are made to haul a load just like the axles on my trailer. 8,000 pound on the truck rear and 14,400 on the trailer pair. To be frank, The load on that trailer looks pretty damn centered to me. It weighs 9,700 pounds and has 2,200 pounds drawbar weight. Run that by your profecient engineer and he will tell you that it is right on the money.

I also realize that most hitches really aren't worth much, that is because most hitches are built by flatlanders for flatlanders. I'm not pulling a fricking pop-up tent and this isn't a MOST hitch. It has about 200 pounds of iron in it. The front end of the truck will come off the ground days before the hitch breaks. The trailer coupler is rated at 5000 (yes five thousand pounds) drawbar weight and 30,000 max trailer load. The ball has an 1.25 inch shank. This cow squeeze isn't even half a load. I only have 6500 pounds on the trailer.

I live at 3500 feet elevation. I cut wood 20 miles from here at 6500 feet. We got two kind of roads around here Up-hill and Down-hill, all of them are rough and half the time they are covered with snow (it snowed today). If you build a trailer so the hitch is equal distant between the rear axle of the truck and the axles on the trailer, you are designing a system that is inherently prone to sway and likely to pull you off the road when one side of the trailer gets caught in a ditch or a snow bank. That won't get it around here.

If you put the hitch near the axle of the truck (Like a semi or 5th wheel) then the trailer will be less likely to sway or affect your truck as the trailer is better controlled by the rear axle.

Right now I own something like 7 trailers. I've probably pulled them, and the other ones I've wore out, well over half a million miles. I forgot more about pulling a trailer than most people will ever have the oportunity to learn.

Some guys drive Fords, Some guys drive a Dodge. I drive a Chevy and I pull a trailer with the axle in the rear.

Respectfully yours,

[stlaser]

You had a problem. A few of the guys on this board and the ones who walk through my shop door with broken down, cobbled up hitches don't know their rear from a toilet drain I was trying to add some insight to your problem. But apparently you already knew that along with eveything else. So again good luck with your problem.

[TROYLV]

i think if you check with a front end person you will find that when the weight transfers to the back the front will elivate which causes your camber to change. this will cause the shimmy at certain speeds. have run into this before.

[Scrub]

Thanks Troy,
I think you hit the nail on the head. Loaded, I had 3500 pounds on the front and it was "OK", but I could feel that was tring to shimmy on a rough part of the road and the stabilizer was preventing any major movement.

I'm gonna put a double stabilizer and a new steering box on it.

THe joy of buying old trucks on e-bay

[Richard]

I doubt you will get much, if any amount of camber change with a Dana 60 front axle. Troy, you must be thinking of a 2wd IFS. The front end would have to be bending to change the camber with a straight axle. Having cupped front tires (common with a straight axle) and the axle being unloaded could have caused the shimmy due to tire wear. Glad the stabilized helped dampen the unwanted movement.

[Mike C]

Camber is the inclination of the spindle relative to the vertical. incrasing load on the rear should INCREASE camber by tilting the spindle further backward. But the problem is weight IMO. There just isn't enough weight on the front end with that trailer. The tires are just barely contacting the road. THis is what causes head shake in a high perf motorcycle as well. Using a load leveler hitch will help transfer weight back onto the front of the vehicle. The best option for pulling a trailer of that size/weight is obviously a gooseneck trailer, but that's big bucks. Go with the distribution hitch and my guess is most of your woes will vanish.

[Scrub]

Thanks for all the help.

As I said, with a new stabilizer, it drove like a dream. The shimmy problem did not occur when I had the cow squeeze on the trailer, it happened the day before with a much lighter trailer and a load on the bed of the truck also. I just took the picture of the truck to show that the problem was fixed and I was able to haul a load without the shimmy problem.

With the cow squeeze loaded, the front axle had 3500 pounds load. I would hope that is plenty of front end weight (sounds like a lot to me) I don't know what the normal front axle weight is, but maybe just a bit more.

What the picture doesn't show very well is that I cut almost 2 feet off the frame and the hitch on the truck is like 30 inches from the center of the rear axle, almost like a gooseneck.
Honest, It won't do wheelies, I've tried :-)

Thanks again.

[Richard]

Mike what you are refering to is caster. An example of negative camber is a lot of the lowered vehicles with the top of the tire angled in. A shopping cart has a lot of negative caster, wanders all over. A motor cycle has a lot of positive caster, very responsive steering. A heavy load would maybe change caster a degree or so more positive by twisting the bottom ball joint forward making the steering a bit more touchy but most likely not as the axle only has about 4-5 degrees positive built into it. Anyways glad the problem is fixed. Sorry for the alignment lesson.

[Mike C]

Oops. I knew that! Obviously camber doesn't change unless the solid axle balljoints are worn! What I meant was that the increased CASTER from the added load would make the vehicle more stable. The added caster causes the vehicle to be less twitchy and the tires to be more inclined to go forward. Sorry for the confusion... I bought a Howe bubble caster/camber gauge about 5 years ago and do my own alignments now. A most excellent investment!