1972RedNeck

1993 Dodge W250. Been working on getting it to drive better for quite some time now. Made a bit of headway, but it's still not where I want it. It just won't self steer like it should. Over the past year or so, I have installed:

new tie rod ends
new drag link
RedHead steering box
new kingpin bushings
new kingpin bearings
new front axle u-joints
new steering box plate
new front springs
new front spring bushings
new swaybar bushings
new shocks
new U-joint in place of the mickey mouse steering shaft coupler

Any part that could negatively affect how it drives, I have replaced. I have adjusted the toe-in to perfection. Tire wear is non-existent on the front.

It drive decent. Still not as good as my last '93 W250 that I had nor as good as any of my other stiff axle push-pull steering vehicles (I.E. crossover steering isn't what I'm looking for). Slightly miffed that it still doesn't drive right, I did some looking and finally found an alignment shop willing to just put it on their rack and give me the readout - which finally shed some light on my problem.

Caster angle on the left hand side was .5° and right hand was just shy of .6° While their book showed this to be within spec, I have found my problem.

More caster makes it self steer better. I need more caster - somewhere in the 5° to 8° range.

How do I go about doing this? Can't use wedges because the passenger side studs for the springs will break, correct? Not sure I'm up to cutting and re-welding the knuckles...

What are my options to get my caster angle up to where it needs to be to drive great?

edwinsmith

Can you change the angle of the springs somehow? I'm just guessing. I've never seen one up close.

jtamulonis

I never heard of the studs breaking. if you`re worried, get some new grade 8 studs and bolts for the passenger side, put the shims in and motor on. I`ve done a bucket load like this and NO problems. get the studs so the coarse end screws in until the shank hits the spring pad. and the fine threads are long enough to stick out of nuts on the spring plate. you may have to cut some of the coarse threads off to get the stud to screw all the way in. I prefer steel shims over aluminum.

oliver foster

I have angled shims under my '72 Power Wagon with Skyjacker 6 inch springs and the same with my '85 crew with Skyjacker 6 inch front springs.
I have never had problems with those studs breaking on either rig and both have been lifted for a long time. The crew for 13 years the '72 for about 20 years.

I agree if you can find the steal shims go with those.
The aluminum ones tend to break and/or corrode over the years.

The other much more work option would be install a drop front leaf spring hanger, like Jungle of at RCC makes or fab up your own.

maybe368

IIRC, it is caster that causes your steering to return to straight after a turn. That said, it is set by the king pin inclination at the drawing table. I recall a post on here where a slotted device is put on the king pins (4WD only, of course) that allows for caster adjustment, I'll try to find it. That said, when my rig started not returning to center after a turn, it turned out to be a broken mount plate. You said that you bought a new one, so, is it possibly not torqued tight enough. I remember NJTman posting the correct procedure for tightening them and also that there was some discrepancy of torque values from different FSM's...Mark

u2slow

Longer shackles increase caster. I built my own... with holes for 5", 6", and 7".

Parabolic leafs update - Ramchargercentral.com

1972RedNeck

IIRC, I thought of this awhile back, but the math said I would have to make the rear shackle about 6" longer (3" of lift) to get 1° - I don't want that much lift.

1972RedNeck

That's encouraging for sure. How many degree shims are you running?

oliver foster

The shims are what they sent from Skyjacker with the lift springs I ordered.

If I am picturing the problem you have correctly...Longer shackles at the back of the leaf spring would make your issue worse.

u2slow

Here's a D60 shim kit... 3 wedges

DIY 4x :: Suspension :: Degreed Axle Shims - 3 pc. set

1972RedNeck

Nope. Bottom of the axle needs to roll forward, top needs to roll back. Longer shackles in the rear would accomplish that, but it looks like I will be going with the 3 piece wedge set.

Alec

I reserve the right to be wrong, but I am pretty sure that it is about 13/16 of an inch additional shackle length per degree.

Or you can buy a couple: MEVOTECH MS500117 adjustable king-pins.

u2slow

That's closer to what I calculated.

I got about 2* extra caster with my shackles. If I needed more, I'd have done a 3-piece wedge setup.

1972RedNeck

Let's go with your math.

But I do really like the adjustable kingpins - more caster without increasing the front driveline angle.

edwinsmith

Yep! To much driveline angle is hard on the U-Joints.