2009 F250 4x4 I've replaced a few things in the front end and have narrowed my front end problems down to two symptoms. First of all, there is a shudder which comes and goes every few seconds while travelling straight down the highway. Second, any time i enter into a prolonged left or right hand curve a wobble starts up. Not the death wobble but sort of a mini death wobble. Looking for suggestions to pinpoint the cause of those two problems. Recent improvements include bilstein damper, center link and tie rod end and track bar bushing . No movement visible in ball joints or tie rod ends.

 

It needs more caster angle. The specs Ford give have a range thats IMHO to broad, it really need to be 5+ degrees. There are bushing in top of the knuckle the upper ball joint goes through that are used to adjust the caster angle (see link below to RockAuto for examples of the part I'm talking about).

Most shops now charge a fixed fee for an alignment (like $79 or something), no way are they taking the time required to pull that rusted in metal bushing out for the fixed alignment fee, they'll just "set the toe and collect the dough". That and of course no shop is going to stock all the various bushings needed for all the different solid axles 4x4 trucks out there either. So it's either two trips to the alignment shop or DIYing it. The only downside to too much caster angle is increased steering effort which of course equals increased stress/ quicker wear on components when steering.

https://www.rockauto.com/en/catalog/...+bushing,13508
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Wow at the options. I'm seeing about 5$ a pair for the cheap ones and $120 a pair for the most expensive. What are the problems with the cheap ones? Also, it seems to me that the two-piece bushings make the most sense. with the one piece you might get the caster you want but the camber could be out or vice versa. BTW, what do you mean by two trips to the alignment shop?

 

One trip to see what the caster is at currently (say its at 1 degree now, which its to low) ,then order the bushing you need to get to 5-8 degrees, then a second trip to the alignment shop to get the bushing put in and the caster verified to be in the right range.

There are multi-sided bushings that can be clocked such that they affect both camber and caster, that first trip to the alignment shop should give the the camber number as well to see if that needs to be adjusted or not.
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He means that you would take your truck in, get it measured to see what bushings the shop would put in to correct it (most don't go for the 'adjustable' ones), then you would leave while they wait on them to come in, which could take a week or more. When the parts come in, you'll schedule another appointment for them to replace the bushings and do another alignment.

 

These bushing have no moving parts so the only quality issues as I see it are manufacturing accuracy and material. Why should anyone choose the high priced ones over the cheap ones?

 

For the reasons you just mentioned, manufacturing accuracy and material.

These parts need to be accurately machined to fit in the knuckle hole, be a perfect cylinder shape, and have the correct taper machined for the ball joint, at the correct angle needed to provide the very small number of degrees' of rotation desired ,and be made of a material that won't egg out or fall apart over time.

Personally I wouldn't use the cheapest Chinese knockoff bushing I could possible get here, especially when even the MOST expensive one is $69 and most are in the $25 range. You're going to pay way more in labor getting that cheap part replaced than buying the slightly more expensive part anyway.
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I appreciate your insight on this matter and especially the fast responses. On another post I found the following:
For an F-250 4x4 with standard suspension. (The model year was not specified)

LH RH Total/Split
Camber 0.15 +/- 0.75 deg 0.15 +/- 0.75 deg 0.0 +/- 0.75

Caster 3.3 +/- 1.2 deg 3.3 +/- 1.2 deg 0.0 +/- 0.55

Factory caster specs would be from -4.5 to +4.5. The adjustable busings say things like +/-2.5 degrees or +/-4.0 degrees. Is that from zero or should I read them as 3.3 +/- 2.5 degrees?

 

Another question, a few months ago I took my truck in for an alignment. i told the front end guy that I wanted him to give it more caster. He told me that he couldn't adjust the caster because it was set at the factory and wasn't adjustable. This was a guy with about 40 years experience. Did he lie to me? Are factory bushings adjustable?

 

What camber should I be looking for?

 

Nope, factory spec (assuming what you posted is accurate, I haven’t checked) would then be 2.1 to 4.5. (Because 3.3 -1.2 = 2.1, and 3.3 + 1.2 = 4.5)

You’d have to figure out what degree bushing is in there now. Very often, but not always, the factory is a 0 bushing. Say if a +2 bushing was in there now, and you wanted to add 4 more, then you'd need a +6 bushing



Yeap, straight lied to you. Probably because he doesn’t want to invest three hours of labor pulling out a rusted in bushing for a $79 alignment charge. I've never seen a factory dana bushing that was clockable for different adjustments, not saying they don't exist, but I've never seen one, and I've played with a lot of 4x4 dana front ends. If it weren't adjustable, then what is that long page of parts on RockAuto for? Adjusting caster this way is NOT a new concept, it's been done for literally decades.



You need more caster angle, not camber. You’re looking for at least 5 degrees of caster, the more the better to a point , steering effort increases the higher you go, target 8 degrees that way if you miss a couple degrees in either direction you’ll still be okay.
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Just for more clarity here is some pictures. The below bushing is a 2 degree one that is clockable (meaning it has flat spots on several sides making it so you can install it in different orientations to give different adjustments and adjust both camber and caster depending on which way you install it). Factory bushing generally only have one flat spot and therefore can only be installed one way.

Here you can see it says 2 degrees on it, most will have something similar, usually stamped in, unless it's just rusted off.




Here you can see how the hole the upper ball joint goes into is not straight, its way closer to the edge on the bottom than the top. This is part of that precise machining the Chinese knockoff bushings may be lacking if you go ultra cheap on these.




No affiliation, but I've had good luck with this brand of made in the USA bushings, although it has been awhile since I've needed/ ordered any.




And here's the instructions they print on the back of the box for how to install / check the alignment.


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While reading the reviews for some of the two-part bushings I'm seeing comments about the alignment shop not knowing how to adjust them. I found one guy who was demonstrating an alignment tool that read camber and caster on levels. It looks as if a DIY guy could do this at home. The trick would be to have the truck perfectly level. The thing is that one guy has the wheel off and is using the face of the brake disk to check camber while another guy has the wheels on and is using swivel bases underneath his tires and a wheel clamp on the rim. One method would be low impact budget-wise while the other would cost you around 4 to 5 Cnotes. I'm not sure just what it take.

 

There are DIY front end alignment tools available if you want to go that route.

I have similar tools to these





They get the job done at home but if you only have one vehicle you're trying to mess with, they may be more trouble than they're worth.

Try to find a repair shop that also does alignments, not just an alignment place, and see what they have to say. It'll certainly cost more than the flat alignment charge, but any halfway decent shop should be able to do it.
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Remove front brake Calipers an check to feel for a rough wheel bearing If you haven't had new wheel bearings installed.
If the truck hasn't been leveled install shocks and raise it one inch at a time. Install a steering stabilizer shock if has been leveled..
If all that stuff is like new I would be looking at Tie Rod ends and Steering unit stuff. Did you hit a large pot hole at interstate
speeds if you can rember it. Lots of potholes around now. Potholes screw with Ford wheel bearings and linkage ball joints.

To know I on the right track, turn your toe=in in 2 turns take it for a 20 mile drive, varying speeds and roads and see if it all disappears, drives great. Turn it back to original and replace bad stuff. Rapid wear occurs to tires scuff. 500 miles may wear out a set. Inspect your front frame and Suspension for dents with a flashlight.


If you feel a sort of steering wheel lock when the death shake happens look to your powersteering. The race and ***** in it get damaged. Look to that part if your ball joints and tie rod ends are all in great shape or bent.

Your wheel bearings are most likely the most economical repair. Although the hardest to replace. Pot holes and heavily salted streets are hard on that right front wheel bearing.
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