Hey guys - Anyone explain having too much positive camber on my sfa?

I just completed a rebuild and now it appears I have too much positive camber (wheels like this \ / ) I didn't change anything in the rebuild - except slightly decreasing the shims on the knuckle/trunion bearings to increase drag - as I measured with a pull scale and setup at about 10 ft/lbs - or about.

In what I've read - there seems to be a ton of different thought on what actually causes positive camber in a toyota sfa and how much if any is acceptable?

Thanks!

 

A couple pics ...

 

So one post in a similar issue thread reads as follows:

Ok Guys I have some details to offer.

First of all the truck is supposed to have some camber. That is the tires out at the top when you look at the truck from the front. This is normal but is influenced heavily by the use of offset wheels or wheel spacers. You are basically moving the wheel out away from the pivot point of the steering which will also "enhance" the camber on the truck. Larger tires also add to the effect as again the top of the tire is farther from the centre of the axle. The angle is the same but the distance is more.

It also effects the "scrub radius" of the axle. If you were able to draw as line straight through the trunion bearings you will find that the lower one is actually slightly farther out then the top and if you extend the line all the way to the ground it should land at the centre point of the tire tread. When you use offset wheels or wheels spacers you move the wheel out of alignment from the this perfect "scrub radius". On a truck it's not a big deal but if you were carving corners on a race car this would make the car push like crazy.

None of this however will make the truck wonder on the road when you are trying to drive in a straight line. For that you must look at the caster angle or the amount of variation in caster angle. Basically the axle is rolling forward and backword when you speed up or slow down or is just way out of wack! If you still have stock steering the roll of the axle will also shorten and lengthen the distance between the steering box and the axle and make the truck turn right when braking as the drag link will force the wheels to turn right.

You need to reduce the roll in the front axle and ensure the axle has POSITIVE caster. Think of a top fuel dragster....they have tons of POSITIVE caster. This meens the axle is tilted backword so the top axle pivot is set back from the lower. Again if you draw an imaginary line through the bearings while looking at the wheel from the side this time and extended it down to the ground the line should touch down ahead of the centre of the tire tread patch.

I will try to add some diagrams to ilustrate this when I get a chance.

Basically don't worry about the camber and pay attention to your caster. Most lifted trucks with taller leaf springs will need shims to set the caster back the proper setting. Negative caster on truck is a bad thing and is very dangerous!

Also if the springs are week or worn out they will create a rolling problem which means the caster angle becomes variable. Even the bigger tires will create enough friction on the road to force the caster out of wack on the highway if the springs are weak. The stock truck has a tie bar to prevent roll but it becomes too short when you add lift springs and many people remove it. You can get away without the tie bar provided you springs are stiff enough to prevent roll when you brake and accelerate. I have made a custom tie bar for my truck which is slightly longer then stock and holds the axle at the proper caster angle.

Also check your drag link for movement. You can actually tighten up the joints if needed. If you have a lift you should also have a dropped and adjustable drag link. If not your steering box is not centered properly and not on the detent (they engineer a "Notch" in the travel a centre to help you drive straight). You can get one of these from Summit racing of all places and they are $70.

That's my five cents on the topic.

Question:
How much positive camber is acceptable if you are in agreement with having some positive camber?