u2slow

Kingpin inclination is inboard/outboard angle.... caster is fore/aft angle.

The former you're basically stuck with, but caster changes as you rotate the axle housing, i.e. lift the pinion up and down.

maybe368

Thanks for straightening me out on that, it has been many years since vocational mechanics school. So inclination means side to side angle and alters camber and the fore aft angle, or inclination is caster, I'm sooo confused ...Mark

u2slow

Been a long time since automechanics class for me too. I've forced myself to keep a working knowledge of it as I do my own steering adjustments and modifications.

Offset bushings (or whatever they call them) for the kingpins can change camber or caster depending on how you clock them. I think we're talking less than a degree of correction here though.

What's important about the kingpin inclination is the angle exists even when the camber is zero. It dictates the scrub radius of the tire. Increase the scrub through negative wheel offset for better handling. A decrease in scrub (i.e. taller tire on stock wheel) tends to have more wander.

nonrev

Ok, so I'm at 3.1 on drivers side and 2.9 on passengers side, so adding 5 degrees would the numbers be 8.1 and 7.9? (sorry I am not real good with front end geometry)

And thank you, Maybe 368, and u2slow for your very informative replies
also would the shims go under the front or rear of the springs, and what would that do to the pinion angle?

u2slow

It does make your front pinion angle slightly worse, and slightly more driveshaft angle. I can't imagine any consequences 0-2" lift.

I run 2" leafs, 1" zero-rate, and 5" shackles (stock is <4") and grinding some lumps off the CV. No binding.

I considered buying wedges, but decided I could make my own shackles instead.

1972RedNeck

This is EXACTLY what my '93 is doing. I have changed every replaceable part that could have even the slightest effect on handling and nothing has fixed it.



Let us know what you find, because it sounds like I need the exact same thing.

nonrev

1972 RedNeck, earlier in my post you said you ordered the bushings, did you get them installed? Did they not help?
Thanks

Vern
BTW, we are on 10+ hour shifts right now so it will probably be Sat before I have a chance to work on the truck

u2slow

Do some googling and read some Pirate4x4 threads on solid-axle caster... 5-10 degrees comes up time and time again.

Did you use the longer shackles that Carrier supplies with those springs? IIRC, they're somewhere between 1/2" and 1" longer than stock, and that's a caster increase.

nonrev

Did you use the longer shackles that Carrier supplies with those springs? IIRC, they're somewhere between 1/2" and 1" longer than stock, and that's a caster increase.[/QUOTE]


No I did not.


What I have decided to do is use the Moog K992 that installs in the lower king pin it looks stronger than the upper kit and more adjustable, best price was from Jegs @ 85.99 each free shipping., as I said earlier I'm at 3.1 on drivers side and 2.9 on pass. side and will set it at 4.2 drivers side and 4.5 on pass. side. The parts will hopefully be here by next Fri. 6/15 and can get them installed, will try using a digital angle gauge to try and get it set right

bigredbrick

This sounds alot like my experience with front axle u-joints. One of the cups could be frozen from corrosion and every now and then the axle shaft will rotate to where the frozen joint will mess with steering. You can be going straight down the freeway and it will suddenly pull to one side. Seriously disconcerting.
Personally, I think your front axle is messed up beyond repair. You better send it to me to take care of disposal!

mknittle

Actually there are tapered shim that change camber/ kingpin inclination.

Dana 60 camber shims, adjustable lower kingpin camber parts, Kingpin parts. - Pirate4x4.Com : 4x4 and Off-Road Forum

u2slow

I know those items exist.... kind of a bandaid, IMO, for a tweaked housing, weak/worn kingpins, etc. Camber tends not be a problem unless its so bad its directly causing uneven tire wear.

EDIT: The last poster in that pirate thread had issues with the K992 part.

peckens

I need to rebuild my front end badly. However, just putting in the borgeson shaft and installing the red head steering g gear made the biggest difference. My tie rods are loose as hell but as my wife says “the steering is as smooth as butter”. It was 4 years ago since I installed the red head and it still is smooth.

nonrev

I think you will find that with most any product, and Pirate 4x4 trends more to people that rock crawl and trail ride their machines IMHO.
I do not believe the housing is bent and I have put many new parts in it. The only thing I have not replaced is the upper king pin itself, they looked good, no rough spots or galling. I used a autozone box because mine was leaking, a borgeson shaft, new pitman shaft, spicer greasable joints which I grease every 5000 miles, no play in the tie rod ends. I feel this thing should drive perfect and for the most part it does... BUT it does not track like it should hence the quest to try most anything to see if it will work. I'm not going to go wild with the caster, just about 1 degree more than the stock setting which is 3.2 left and 3.5 on the right, if that doesn't do it I will replace the housing. I truly appreciate all the thoughts and discussions this thread has had as I have definitely learned more about alignment issues on these front-ends than the typical "just set the toe and it will be fine" that most people think, again thank all of you for replying.

u2slow

IMO, you're on the wrong track. When the caster matches side-for-side, it's not a housing problem. Its how its installed/positioned in the vehicle.

Chevy specs 6 degrees caster on identical Dana 60 outers. Hmmm....