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Aaron S
12-06-2012, 06:12 PM
I talked to Marty a lot on the phone trying to solve a bumpsteer issue. I figure ile put some pictures of the customish trac bar bracket myself and a friend put together to solve the problem per Martys recomendations and my testing. Hopefully he dosent put the pics in the Why File.

Layson
12-06-2012, 06:30 PM
Is that a PSC ram in there? Who's track rod is that?

Aaron S
12-09-2012, 10:03 AM
Yes on the PSC ram assist modded box and PSC ram.

The trac rod is Icon.

07_powerstroke
12-09-2012, 03:19 PM
I gave up I'm still thinking I have bumpsteer on bigger bumps when the road is uneven good luck to you

Aaron S
12-09-2012, 04:28 PM
I gave up I'm still thinking I have bumpsteer on bigger bumps when the road is uneven good luck to you

I definitly hear where your coming from.

I took me hanging my truck from a crane by the tow hooks then removed parts so I could get the coils out. Once the coils were out I locked the tie rod down then raised the truck up and down to try to get an idea as to what the problem was based on what Marty told me. Hes why I took the four link off and put the ALAs on. I ended up adjusting the ALAs all over the place with no improvement. I probably tried something like this five times. It came down to changing the upper mounting position of the trac bar, which led to modifying a skyjacker trac bar bracket to suit my needs.

07_powerstroke
12-09-2012, 06:04 PM
I definitly hear where your coming from.

I took me hanging my truck from a crane by the tow hooks then removed parts so I could get the coils out. Once the coils were out I locked the tie rod down then raised the truck up and down to try to get an idea as to what the problem was based on what Marty told me. Hes why I took the four link off and put the ALAs on. I ended up adjusting the ALAs all over the place with no improvement. I probably tried something like this five times. It came down to changing the upper mounting position of the trac bar, which led to modifying a skyjacker trac bar bracket to suit my needs.

I don't feel like dealing with any of this truck stuff anymore I guess I'm going to just deal with it my complaints are #1 no matter what I do the rear drive shaft vibrates or studders 0-10 MPH #2 rides very very rough on dirt roads pot holes ect... #3 pulls to right but I haven't had a professional alinement if someone offered me decent money for the lift and tires I would sell it to go to stock

DFW64
12-09-2012, 06:28 PM
The best thing I did was buy a sport camera and mount and identify the issue on video.

You can drive yourself crazy trying to fix these problems. Helps to have some concrete evidence of the problem.

What's the bumpsteer like? What kinds of terrain does it occur on? Is there steering wheel feedback? When's the last time you changed the trac bar ball joint?

07_powerstroke
12-09-2012, 06:48 PM
Steering wheel does not move so i thought it was body roll but its not I believe it is bumpsteer am I correct? The road is eneven and bump I live in the mountains so the roads are not the greatest... I'm just going to live with it... for the most part the truck is nice to drive.

DFW64
12-09-2012, 06:59 PM
Steering wheel does not move so i thought it was body roll but its not I believe it is bumpsteer am I correct? The road is eneven and bump I live in the mountains so the roads are not the greatest... I'm just going to live with it... for the most part the truck is nice to drive.

Honestly, I'm not sure. My comment was directed more towards Aaron S because we have similar setups.

I think my advice from the previous post still applies. Try to pinpoint where it occurs on video and go from there.

Aaron S
12-10-2012, 03:26 PM
The problem is not to bad at this point, since ive made the new upper trac bar bracket.

I apologize if im using the incorrect word by saying bumpsteer. The issue was and still slighlty is, the steering wheel will rotate, steer, oscilate in my hands when going over bumps, most noticable at highway speeds. The handling of the truck is not a problem, it steers where I want when I want.

The situations that this occurs now is when I travel over roads and bumps are not even all of the way accross. Imagine going over a speed bump that is at a perfect 90 degree angle to the road, both front tires hit the bump at the same time. In this situation the steering wheel does not rotate. Now if the speed bump is at a 45 degree angle to the road. The right front tire hits the speed bump first, the steering wheel will turn to the left then when the left front tire hits the bump the steering wheel will turn to the right. Thats the jist of it.

I havent driven another truck with the same setup as mine, so maybe this is acceptable and im just to damn picky.

Aaron S
12-10-2012, 03:38 PM
I don't feel like dealing with any of this truck stuff anymore I guess I'm going to just deal with it my complaints are #1 no matter what I do the rear drive shaft vibrates or studders 0-10 MPH #2 rides very very rough on dirt roads pot holes ect... #3 pulls to right but I haven't had a professional alinement if someone offered me decent money for the lift and tires I would sell it to go to stock

It definitly sucks when you get to the point of scrapping the lift. My truck had eight inches of leaf spring lift at one point and rode horrible. Lifting trucks seems kind of like horsepower the higher you go and the price goes up exponentially, if you want a proper working good riding setup. Im always tempted to go higher, but with 35s, it dosent need regeared and rides pretty good without to many nagging problems over all.

Aaron S
12-10-2012, 03:41 PM
The best thing I did was buy a sport camera and mount and identify the issue on video.

You can drive yourself crazy trying to fix these problems. Helps to have some concrete evidence of the problem.

What's the bumpsteer like? What kinds of terrain does it occur on? Is there steering wheel feedback? When's the last time you changed the trac bar ball joint?

Ive never replaced the trac bar ball joint, it always seems tight when ive checked it.

It would be interesting to see what is going on on a video but I just can imagine being able to see what is causing the problem.

Erikclaw
12-10-2012, 03:53 PM
I don't feel like dealing with any of this truck stuff anymore I guess I'm going to just deal with it my complaints are #1 no matter what I do the rear drive shaft vibrates or studders 0-10 MPH #2 rides very very rough on dirt roads pot holes ect... #3 pulls to right but I haven't had a professional alinement if someone offered me decent money for the lift and tires I would sell it to go to stock

#1 for me it had to be a cv drive shaft but then it failed prematurally. Now I run a one piece and had no shutter with either. I adjusted a non rear cv from here to the moon and always had a shutter like you describe.

Layson
12-10-2012, 04:02 PM
Hope Dave can help you out. I am thinking it has got to be your track rod bracket... If it got better from start to finish than maybe that is it. Something is just slightly out of whack. I am going to throw up a couple pics that you have seen of my buddies setup. Just for anybody else out there... 08 axles on 2000 truck, stock 05 track rod bracket, stock 08 steering box, OUO Ala's and OUO traction bars. 4.5" Icon...

Like I said Dave is a wealth of knowledge and hopefully he can help you out.

http://i355.photobucket.com/albums/r447/laysonw/image-3.jpg

http://i355.photobucket.com/albums/r447/laysonw/image-2.jpg

http://i355.photobucket.com/albums/r447/laysonw/image-1.jpg

DFW64
12-10-2012, 04:23 PM
Ive never replaced the trac bar ball joint, it always seems tight when ive checked it.

It would be interesting to see what is going on on a video but I just can imagine being able to see what is causing the problem.

Don't discount the power of video. I can mount the camera to the dual steering stabilizer and have it inches away from the joint on the frame or the one on the axle. Its not crystal clear HD, unless its a fancy GoPro, but its clear enough to see. Then you can do that fancy Carli stuff and have split screen viewing of the problem.

We can sit here all day long and spitball ideas on whats happening, which I'm more than willing to do, but having something to point out on video sure makes it alot easier.

That's how Dave helped me pinpoint my bumpsteer issues.

DFW64
12-10-2012, 04:30 PM
Ive never replaced the trac bar ball joint, it always seems tight when ive checked it.

It would be interesting to see what is going on on a video but I just can imagine being able to see what is causing the problem.

Depending on the mileage and driving habits, it might be time to replace. Those things are a couple of notches above junk.

Layson
12-10-2012, 05:35 PM
Depending on the mileage and driving habits, it might be time to replace. Those things are a couple of notches above junk.

I agree! I think I would start with that lower joint in the axle first!

Zmann
12-10-2012, 05:53 PM
. I'm just going to live with it... .

you need to tip your Avatar right side up .. I know that will help :D

http://powerstrokearmy.com/forums/image.php?u=785&dateline=1326770167

DFW64
12-10-2012, 06:04 PM
I agree! I think I would start with that lower joint in the axle first!

Yes sir...can get them around here for $70.

Cory S
12-10-2012, 06:15 PM
i dont know if this could cause it but what is the length of your track bar in comparison to your drag link? (steering arm)..

Aaron S
12-10-2012, 06:50 PM
Yes sir...can get them around here for $70.

So no signs of any slop or wear and your thinking it might be a problem?

The trac bar is close to two inches longer than any other truck using the same bar at 2.5 inches of lift. Look at the exposed threads in my pics vs the truck in Laysons pics.

It will probably take one of two things to get me to start changing things on my truck again to solve this potential problem: drive an identical truck suspension wise or talk to Dave Hoppert.

For the sake of my knowledge answer this question for me DFW. When driving your truck, do rough road conditions ever cause your steering wheel to steer/ move around in your hands?

DFW64
12-10-2012, 07:43 PM
So no signs of any slop or wear and your thinking it might be a problem?

The trac bar is close to two inches longer than any other truck using the same bar at 2.5 inches of lift. Look at the exposed threads in my pics vs the truck in Laysons pics.

It will probably take one of two things to get me to start changing things on my truck again to solve this potential problem: drive an identical truck suspension wise or talk to Dave Hoppert.

For the sake of my knowledge answer this question for me DFW. When driving your truck, do rough road conditions ever cause your steering wheel to steer/ move around in your hands?

First, call Dave.

This all depends on your definition of "rough". Are we talking about messed up concrete or gravel/offroad conditions?

On messed up concrete, no the steering wheel does not move around. I'm assuming you are referring to unwanted feedback?

For gravel/offroad conditions, I can't say because I haven't tested the suspension with the new tires. My old Nittos were junk and vibrated badly on gravel and dirt roads.

Sometimes, at speeds under 10, I can experience some slight feedback when going over rough concrete. Its minimal and sporadic and most likely due to the worn out stock drag link.

Can you feel anything in the floorboard when it happens? Does the steering wheel kick or jerk in a certain direction.

DFW64
12-10-2012, 07:52 PM
So no signs of any slop or wear and your thinking it might be a problem?

The trac bar is close to two inches longer than any other truck using the same bar at 2.5 inches of lift. Look at the exposed threads in my pics vs the truck in Laysons pics.

It will probably take one of two things to get me to start changing things on my truck again to solve this potential problem: drive an identical truck suspension wise or talk to Dave Hoppert.

For the sake of my knowledge answer this question for me DFW. When driving your truck, do rough road conditions ever cause your steering wheel to steer/ move around in your hands?

I did notice that the trac bar length looked irregular, but then again your using a 2005 mount correct, so I don't know if they should match up in length.

You can unbolt the trac bar from the ball joint and check for play. A little bit of play can cause problems.

GreenMachine
12-10-2012, 07:55 PM
My 05 does what you described Aaron, the wheel will walk in my hands if say only one tire hits a frost heave. Or if only one tire hits a pot hole. The truck will go where i point it, but when it hits bumps it does all kinds of crazy chit.

I talked for a while with Cary OBSWIZ today and ended up ordering caster adjustment shims and a adjustable track bar because we believe thats the culprit of my issues.

My truck has a leveling kit from the PO and i think it wasnt aligned properly. Hopefully this will get the Caster correct and recenter the axle properly.

DFW64
12-10-2012, 08:23 PM
My 05 does what you described Aaron, the wheel will walk in my hands if say only one tire hits a frost heave. Or if only one tire hits a pot hole. The truck will go where i point it, but when it hits bumps it does all kinds of crazy chit.

I talked for a while with Cary OBSWIZ today and ended up ordering caster adjustment shims and a adjustable track bar because we believe thats the culprit of my issues.

My truck has a leveling kit from the PO and i think it wasnt aligned properly. Hopefully this will get the Caster correct and recenter the axle properly.

Can't use caster shims with OUO Ala's.

zj96sc
12-10-2012, 08:33 PM
In general you will fight bump steer issues any time the drag link and track bar are different lengths and/or different angles. Both swing in an arc from the pitman or frame joint - the second those arcs are unequal (either through radius or angle) axle position will change relative to pitman position - ie bumpsteer.

Usually a drop track bar bracket will help, but it needs to usually be matched with a drop pitman. Long story short do what you can to get the pivot points for both as close to each other as possible.

Also make sure your caster is within spec and that you've got a healthy steering dampener. Once the fundamental geometry is correct those two should help the manners and keep those heavier tires in check.

You can also try playing with your front tire pressure a few psi in either direction if you're getting poor performance on washboards/rutted dirt.

Good luck
paul

GreenMachine
12-11-2012, 09:44 AM
Can't use caster shims with OUO Ala's.

Gotcha. My bad.

SAK
12-11-2012, 10:56 AM
Can't use caster shims with OUO Ala's.

Yes you can.

Layson
12-11-2012, 12:53 PM
So no signs of any slop or wear and your thinking it might be a problem?

The trac bar is close to two inches longer than any other truck using the same bar at 2.5 inches of lift. Look at the exposed threads in my pics vs the truck in Laysons pics.

It will probably take one of two things to get me to start changing things on my truck again to solve this potential problem: drive an identical truck suspension wise or talk to Dave Hoppert.

For the sake of my knowledge answer this question for me DFW. When driving your truck, do rough road conditions ever cause your steering wheel to steer/ move around in your hands?

That is your problem if you track rod is 2" longer.... I am thinking you need the 05 track rod bracket....

DFW64
12-11-2012, 01:54 PM
Yes you can.

I should have been more specific, they are redundant are they not?

Marty took mine out when I was there...

SAK
12-11-2012, 02:21 PM
I should have been more specific, they are redundant are they not?

Marty took mine out when I was there...

In a way yes, but you have to have the cams in there or the ball joint would have nothing to hold it in place.

You have to keep the ALA's the same length on both sides when you are adjusting them, if you do not you will be trying to twist the axle(which will wear the 4 big bushings on the axle). After you get you caster set you may need to make some adjustments from one side to another, so this is where you would use different degree of cams to get it to where you want. I.E. more caster on the passenger side to help with the truck pulling to the left.

DFW64
12-11-2012, 02:38 PM
In a way yes, but you have to have the cams in there or the ball joint would have nothing to hold it in place.

You have to keep the ALA's the same length on both sides when you are adjusting them, if you do not you will be trying to twist the axle(which will wear the 4 big bushings on the axle). After you get you caster set you may need to make some adjustments from one side to another, so this is where you would use different degree of cams to get it to where you want. I.E. more caster on the passenger side to help with the truck pulling to the left.

Gotcha...think I was referring to those cams you get with the Icon leveling kit.

Aaron S
12-11-2012, 04:15 PM
That is your problem if you track rod is 2" longer.... I am thinking you need the 05 track rod bracket....

This is what I originally had on the truck. The track rod bracket off of the same truck that I got the axles out of. At least as far as I could tell it is factory, I still have the thing. It has a ford symbol stamped in it somewhere. Unless there were different trac rod brackets for the 05-07 trucks.

The only other posibilities I see as far as it being a geometry issue is if the balljoint area on the axle I have is bent in some way, but ive never been able to see anything that would indicate this.

The reason the trac rod bracket is longer is because I made the bracket to require a longer rod length. All based on a recomendation. In trying to visualize the geometry of the front end in my head im starting to think it was a mistake to make it requiring a longer rod length. That may be causing this issue.

Aaron S
12-11-2012, 04:19 PM
First, call Dave.

This all depends on your definition of "rough". Are we talking about messed up concrete or gravel/offroad conditions?

On messed up concrete, no the steering wheel does not move around. I'm assuming you are referring to unwanted feedback?

For gravel/offroad conditions, I can't say because I haven't tested the suspension with the new tires. My old Nittos were junk and vibrated badly on gravel and dirt roads.

Sometimes, at speeds under 10, I can experience some slight feedback when going over rough concrete. Its minimal and sporadic and most likely due to the worn out stock drag link.

Can you feel anything in the floorboard when it happens? Does the steering wheel kick or jerk in a certain direction.

Im refering to rough asphalt and concrete highways. I dont notice anything in the floorboards of the truck or any loose feeling at all. I tried to explain the feedback in the wheel in another post. Essentially the right side compresses and the steering wheel turns left, the left side compresses and the steering wheel turns right.

Layson
12-11-2012, 05:02 PM
This is what I originally had on the truck. The track rod bracket off of the same truck that I got the axles out of. At least as far as I could tell it is factory, I still have the thing. It has a ford symbol stamped in it somewhere. Unless there were different trac rod brackets for the 05-07 trucks.

The only other posibilities I see as far as it being a geometry issue is if the balljoint area on the axle I have is bent in some way, but ive never been able to see anything that would indicate this.

The reason the trac rod bracket is longer is because I made the bracket to require a longer rod length. All based on a recomendation. In trying to visualize the geometry of the front end in my head im starting to think it was a mistake to make it requiring a longer rod length. That may be causing this issue.

So the one you have on your truck now is the stock one that came with the 2002 truck. You have the 2005 stock track rod bracket sitting around somewhere.

Aaron S
12-11-2012, 05:09 PM
So the one you have on your truck now is the stock one that came with the 2002 truck. You have the 2005 stock track rod bracket sitting around somewhere.

The trac rod bracket that is on the truck now started out as a skyjacker two inch drop bracket that was highly modified by myself and a friend. Im pretty sure it was skyjacker atleast.

My modified bracket was originaly intended for the 05 to 07 trucks.

Aaron S
12-17-2012, 05:32 PM
Video of what the steering wheel is doing on a rough/ uneven bridge crossing at about 65 mph. Seem normal or not?


http://www.youtube.com/watch?v=-n8Gc1rxNoU