alignment question?

[texastrendz]

I have a 1 ton dually that has custom upper and lower control arms and that has been back halfed with a triangulated four link. I have not found an alignment shop that will touch it. I have got the toe and camber pretty good on the truck but it pulls pretty hard to the right. I have read that the caster can cause pull in the vehicle. I have the rearend nice and square in it as far as a tape measure can measure. Do i need to buy a caster guage to set this up or is there any way around this to set the caster? How many degrees is a streetable setup have in it? Any and all help would be appreciated, thanks Daniel. It is a 88-2000 body style.

[robnolimit]

It's time for you guys to buy a caster/camber guage. If it's for dually wheels or a lot of 'big' wheels, - 22+ -, then I would get a wheel lip type, not a spindle or hub type. You can make simple turning plates, 4 pices of 16ga. steel or alum, 16" x 16". put greese between two plates and set under the tire, one set per side. Get a lazer level from Home depot/Lowes to help square up the front/rear. Once you start doing this your self, you won't trust anyone else.

[oldspowered67C10]

You can adjust all 3 angles w/o buying a gauge. I'm not going to go into measuring camber and toe at home as both are done very easily but Ill tell you how I do caster at home.

Caster is the biggest influence in regards to a pull to left or right but just to be sure, swap the front tires side to side to make sure you don't have a bad tire(s) causing radial pull.

After you eliminate the tires as the cause of the pull you can begin to play with caster. Remember this, the car always pulls to side w/ less caster. When I do alignments, especially on RWD vehicles, I try to get .5 degree more caster on the right than on the left causing the vehicle to have a slight left drift to compensate for road crown.

After you know how caster effects how a car drives you can adjust it w/o having to measure it. Since you say yours has pretty bad right pull Id start trying to add caster to the right side by moving/adding/removing shims. To increase caster you need to move the upper ball joint rearward increasing the rearward tilt of the spindle. Start taking shims from the rear stud and adding them to the front stud while maintaining camber as close to how it was as possible.

Then reset toe, re-check camber and test drive checking to see how it changed. If you're where you want, great, if not make another caster adjustment using what you've learned from the first time. Repeat until you get what you want. I know, not the quickest process but a good set of gauges are pretty expensive.

You can actually do it pretty quick if you set up a string box and mark where the tire sit within it so you can adjust toe quickly w/o having to reset the strings. Also, when you want to adjust the shims, jack up the side you want to adjust under the lower ball joint, thatll take all the load off the upper control arm making the shims easier to remove.

Ideally you'd rather increase caster on the right rather than decreasing it on the left because these trucks came with relatively small amounts of positive caster, causing tight turning circles and light steering effort but making them a bit nervous at modern highway speeds. If you run out of adjustment on the right and it still pulls right start decreasing caster on the left side.

[texastrendz]

Nice idea on the turning plates. I would like to get a caster guage for this and was wondering if you had any recommendations since i just want to buy it once. And yes I am running a 22.5 wheel that has been spun down to a 22.
I cannot swap the wheels since they are directional. I am pretty sure it is not a radial pull, it is a pretty heavy pull. I might try adding caster to the right side as long as the wheel does not get into the firewall. The wheels are pretty close to the firewall, I have recessed the firewall already for clearance.