Wandering on road

[opie74]

If you have lifted the front, your caster is out. Post up your alignment numbers. The shop may tell you caster is not adjustable on these, but there is some adjustment in the lower control arm adjusters. Not much and depending on how much you have lifted it, maybe not enough. IIRC, specs call for about 3 degrees.

Caster is the angle to which the steering pivot axis is tilted forward or rearward from vertical, as viewed from the side. If the pivot axis is tilted backward (that is, the top pivot is positioned farther rearward than the bottom pivot), then the caster is positive; if it's tilted forward, then the caster is negative.

Positive caster tends to straighten the wheel when the vehicle is traveling forward, and thus is used to enhance straight-line stability. The mechanism that causes this tendency is clearly illustrated by the castering front wheels of a shopping cart (above). The steering axis of a shopping cart wheel is set forward of where the wheel contacts the ground. As the cart is pushed forward, the steering axis pulls the wheel along, and since the wheel drags along the ground, it falls directly in line behind the steering axis. The force that causes the wheel to follow the steering axis is proportional to the distance between the steering axis and the wheel-to-ground contact patch-the greater the distance, the greater the force. This distance is referred to as "trail."

This is mine after installing SPC upper control arms. I set the arms for +2 degrees of caster over stock and they hit about right on. So with the stock arms and 2.5" of lift in the front, you are running around 1 degree of caster. Thats an imaginary line between your upper ball joint and lower ball joint of almost vertical.

 

[CarmMontana]

I have the alignment paperwork somewhere. I'll find it and post the results.

The tires are Toyo open country's at 265 75 15's.

 

[cj80cruiser]

Are any of you guys that replaced your steering rack guides using the polyurethane kits from wheelers?

 

[curtperry]

Are any of you guys that replaced your steering rack guides using the polyurethane kits from wheelers?

I think you meant polyurethane rack bushings from wheelers. I installed those last weekend and also installed a new 2001 Tacoma rack guide (updated style with no roller) this week.

There has been some improvement in the feel of the steering at low speeds, but on the freeway it still wanders.

My current suspect is the slip joint in the column because, using the procedure that nelsonmd referred to above, I still feel a VERY small click in column when turning the wheel back and forth. Maybe that's enough play to cause the problem... I'll find out.

 

[ToyTec Lifts]

X2 on the alignment printout. The specs we normally recommend are to set the camber to zero and the toe to 0.04 degrees and add as much caster as possible without sacrificing the camber.

Alot of the time, there is not enough adjustment left so the caster will be on the low end which can cause wandering. The fix for this is a new UCA that has more caster built into it.

-Dylan

 

[cj80cruiser]

I think you meant polyurethane rack bushings from wheelers. I installed those last weekend and also installed a new 2001 Tacoma rack guide (updated style with no roller) this week.

There has been some improvement in the feel of the steering at low speeds, but on the freeway it still wanders.

My current suspect is the slip joint in the column because, using the procedure that nelsonmd referred to above, I still feel a VERY small click in column when turning the wheel back and forth. Maybe that's enough play to cause the problem... I'll find out.

Yeah, still had guides on the brain from earlier reading.

 

[opie74]

X2 on the alignment printout. The specs we normally recommend are to set the camber to zero and the toe to 0.04 degrees and add as much caster as possible without sacrificing the camber.

Alot of the time, there is not enough adjustment left so the caster will be on the low end which can cause wandering. The fix for this is a new UCA that has more caster built into it.

-Dylan

This is not a sales pitch. The arms brought my front end back under control. And this is after I threw a butt load of money at replacing everything else.

IMO the suggestions to start replacing things after a lift is put on should be taken with a grain of salt. Get it aligned and see where your caster is sitting. If it did not wander prior to lift, then parts are not worn out.

 

[CarmMontana]

Well guys

I feel pretty stupid about this but it looks like the buddy I trusted to do the alignment isn't all he is cracked up to be. The numbers are all over the place and after looking at what they should be I am sure that a good alignment should fix my problems... lame

The numbers read out like this:

Left Front
Camber
actual= .76 Before= .76
Caster
actual= -.42 Before= -.42
Toe
actual= .11 Before= -.64

Right Front
Camber
Actual= .31 Before .33
Caster
Actual= .06 Before= .06
Toe
actual= .10 Before= -.56

So after looking at the ranges and reading that the caster and camber should read the same left to right Im a little pissed. Anyway is this my issue? Thanks Guys

 

[opie74]

Numbers don't appear to be to far out of spec. Other than the caster which you can not bring back with just the lower arm adjusters. The ability to have the vehicles steering self center will diminish the closer the caster angle approaches 0. This will cause the wandering. The lower adjusters dont appear to have been touched, but with the camber numbers within spec, they probably did not see the need to touch them to try to bring some caster back. The alignment shop I went to said the caster on these is not adjustable.

 

[CarmMontana]

Opie, not trying to disagree but according to my fsm that's just not true. I attached the page on camber and caster adjustment. I am not sure how much it will help but it is definitely adjustable.

 

[opie74]

Opie, not trying to disagree but according to my fsm that's just not true. I attached the page on camber and caster adjustment. I am not sure how much it will help but it is definitely adjustable.

Oh... I know its adjustable. I should have clarified. The shop I took it to is a Belle Tire, and their "expert" said the caster is not adjustable.

The issue you will run into is there is not enough adjustment in the lower arm to bring the caster back into spec. There are 2 options, aftermarket upper control arms that have some additional caster built into them, or put it back to stock.

There is a third option I forgot about, have the lower adjusters maxed out to bring as much caster back as possible, and live with it. Seems alot of folks go this route as Ive noticed there is only a small percentage of folks that have lifted, that want to fix the wandering issue.

 

[CarmMontana]

That makes sense, opie. I understand what your saying now. That being said I got under the truck tonight and looked at the washers and I am not sure what I am really looking at. There are a ton of hash marks and the center line that is set at about the center of the marks. I have been reading a ton of caster adjustment threads and still don't fully understand how the two bolts control both caster and camber... i know they are cams that change progressively as you turn them but its all so confusing.

I am heading on a trip to Colorado in a few days and really want to get this thing figured out. It's gonna suck pulling my pop up if I am all over the road all day... not to mention the wife isn't gonna want to drive ( that means no naps for me! :bash

So other than upper control arms would it be beneficial to take it to the alignment shop and see if they can get a bit of caster to make it track a little better? I just don't want to pony up more cash just to get moderate results.

Also i read a few threads on doing a driveway alignment... is that as crazy as it seems?

 

[opie74]

The adjusters essentially change the position of the lower control arm relative to the upper arm and frame. They can move the arm inward and outward of the frame. Thats how they adjust camber. To adjust caster, you have to move the theoretical line between the upper ball joint and lower, ball joint. To do this you have to move the lower ball joint either forward or backwards. You can accomplish this rotating one adjuster one way, and the other the opposite direction. If you think of a vertical line being 0 degrees (which is close to where your rig sits now), with the top of the line (upper ball joint) being stationary, you need to move the bottom of the line (lower ball joint) forward enough to get as close to 3 degrees as possible.

Years ago before they had alignment machines, they were done with a tape measure. As long as you have the tools available and you know what you are doing, you can do a "driveway" alignment. Ive never ventured down that path, though. And if you have never done it and you are leaving in a few days, I would not suggest this is the time to learn.

 

[Nelsonmd]

That makes sense, opie. I understand what your saying now. That being said I got under the truck tonight and looked at the washers and I am not sure what I am really looking at. There are a ton of hash marks and the center line that is set at about the center of the marks. I have been reading a ton of caster adjustment threads and still don't fully understand how the two bolts control both caster and camber... i know they are cams that change progressively as you turn them but its all so confusing.

I am heading on a trip to Colorado in a few days and really want to get this thing figured out. It's gonna suck pulling my pop up if I am all over the road all day... not to mention the wife isn't gonna want to drive ( that means no naps for me! :bash

So other than upper control arms would it be beneficial to take it to the alignment shop and see if they can get a bit of caster to make it track a little better? I just don't want to pony up more cash just to get moderate results.

Also i read a few threads on doing a driveway alignment... is that as crazy as it seems?

I was the one talking about a driveway alignment, and it can be done, but it is best served as an approximate alignment to get you to the tire shop for a real alignment. You can't really easily measure caster yourself either, so I don't think it is going to help you here.

BTW, I am not surprised your buddy did a bad job on the alignment. Shops usually don't touch camber or caster, even if they are a little out of spec, because they actually have to look up how to do it on every vehicle. Unless you get a very good alignment tech, you will probably have to tell them how to adjust caster on these things, and watch them do it.

 

[nevada]

That makes sense, opie. I understand what your saying now. That being said I got under the truck tonight and looked at the washers and I am not sure what I am really looking at. There are a ton of hash marks and the center line that is set at about the center of the marks. I have been reading a ton of caster adjustment threads and still don't fully understand how the two bolts control both caster and camber... i know they are cams that change progressively as you turn them but its all so confusing.

I am heading on a trip to Colorado in a few days and really want to get this thing figured out. It's gonna suck pulling my pop up if I am all over the road all day... not to mention the wife isn't gonna want to drive ( that means no naps for me! :bash

So other than upper control arms would it be beneficial to take it to the alignment shop and see if they can get a bit of caster to make it track a little better? I just don't want to pony up more cash just to get moderate results.

Also i read a few threads on doing a driveway alignment... is that as crazy as it seems?

am i reading that correctly? the cam is centered?

if there is still room for adjustment, they can add more caster.

as said above, sometimes all the adjustment gets used to bring the camber in, its a lot more important in regard to tire wear. so when you have to choose between them, you pick camber first.

 

[CarmMontana]

Well I went and got it aligned at a reputable shop and was able to give them the numbers and expectations that I wanted and man what a difference. Drives really well now . Guess alignments aren't all equal. Thanks for all the help.

 

[nevada]

Well I went and got it aligned at a reputable shop and was able to give them the numbers and expectations that I wanted and man what a difference. Drives really well now . Guess alignments aren't all equal. Thanks for all the help.

glad you got it fixed, and driving good.

 

[curtperry]

This is a couple weeks old now but since this thread will be a search result for "wandering" I wanted to come back and add my solution here.

These items made my steering feel better overall but did not fix highway wandering:

• Rack Guide (newer cup style)
• Rack Bushings (energy suspension poly kit from wheelers)
• Modified slip joint in column (added roll-pin)
• shimmed the plastic-ball/U-joint in column

What fixed it:

• Replaced Inner and outer tie rods (inners were shot)
• Got an alignment that brought the caster back into spec (from -1 to +2 on each side)

Thanks everyone for contributing.