Steering geometry

Camtron · Mar 9, 2021

So, when I bought my car, I had a friends family shop put in new ball joints and tie rod ends and do an alignment. Flash forward two years, my front right tire wears on the shoulders, my steering has gotten sketchy at best and yesterday pulling off the freeway, there was popping from both sides every time I hit the brake, accelerated or turn the wheels.
Last night, I ordered new tie rods, ball joints and pitman and idler arms and got everything pulled off the car. Will be picking up the new parts this afternoon.
Now, I’m in need of some guidance on how to set things up in the garage to at least get me in the ballpark so, I can drive it to an alignment shop and have it dialed in on a rack.
I can afford parts and an alignment but, shop labor isn’t in the budget at the moment to have everything taken care of at a shop.

Thanks for any help.

Lightning II · Mar 9, 2021

On the FR tire, how’s the air pressure? Normally the camber being off will affect the inside or outside shoulder, but not both.

EDIT: on getting the toe set, get a tape measure or two, and a pair of short boards.

Camtron · Mar 9, 2021

Lightning II said:
On the FR tire, how’s the air pressure? Normally the camber being off will affect the inside or outside shoulder, but not both.

EDIT: on getting the toe set, get a tape measure or two, and a pair of short boards.

Air pressure is at 35psi on all 4 corners. Both shoulders of the RF tire are worn bald. Center tread looks brand new in comparison.

Sub03 · Mar 9, 2021

I did a homemade alignment setup last summer, after a complete rebuild of the front end. The idea was to get the car on the road so I could get it to a shop, but it turned out OK so I forgot all about it.

I used a pair of metal plates with grease between them for turntables. For camber/caster measurement I cut two pieces of 1x1 inch square bars so the fit exactly over the rim lip without touching the tire. I strapped the bars vertically on the front wheels and used a digital angle finder with a magnet to measure.

For camber it's straight forward, just measure the angle on the wheel relative to the garage floor, wheels pointing straight ahead (important with a straight an leveled floor).

For caster you turn the front wheels 20 degrees one way, read angle, turn wheels 20 degrees the other way, read angle. Take the difference between the measurements and multiply by 1.5 (think it's 1.43 to be exact).
That's roughly your caster value.
(e.g. left wheel turned right=91 deg. left wheel turned left=88,5 deg 91-88.5x1.5=3.75 caster)

The real pain is to get both camber and caster right, because fiddling with one affects the other.... U need a lot of patience and at least a six pack for that one.

For toe i did the tape measure thing like Lightning II said.
Remember to set the front ride height before you do anything else.

Camtron · Mar 9, 2021

Any tip for moving/positioning the upper control arm for camber/caster? Like what would be a good tool for moving/positioning the upper control arm?

Sub03 · Mar 9, 2021

I got a Mopar camber/caster adj tool from eBay.

Miller Detroit camber-caster adjusting tool | eBay

But even with the tool it was a struggle to move the control arm in with the weight on the wheels.

Btw: this is the angle measure thingy I used:

DXL360S Digital Protractor Inclinometer Dual Axis Level Box 0.01° Hi-resolution | eBay

Aspen500 · Mar 9, 2021

What I use to get camber close, before aligning it on the machine, is a level with a pair of bolts attached to meet up with the lip of the wheel. Set it so the plumb bubble is centered and you'll be darn close. As mentioned, tape measure to set preliminary toe.

I check it, then guestimate how much the arm needs to move, then take most of the weight off, while still having the arm off the travel limiter bump stop. Then move it, tighten the nuts down and recheck. This requires rolling the car back a few feet and then forward to normalize the suspension, unless you have turn plates or something similar. I have one of the tools to move the arm but don't use it on my Aspen. Too much chance of scratches and chips

None of that does caster, however, if you "dial in" as much as you can while also having the camber close, it'll be surprisingly good. Caster doesn't wear the tires so it isn't that critical until a proper alignment is done.

BudW · Mar 11, 2021

The Toe needs to be very last step - but it does help to have toe eyeballed at the beginning.

The last four front end rebuilds I've performed (at home) were only eyeballed/guessed at, and all four were pretty close when sent to get aligned. I'm pretty astonished by that - if you knew just how blind I am.

Camber is the main tire wearing angle - and generally only on one side of the tire. Toe in/out is the second tire wearing angle.
BudW

Camtron · Mar 11, 2021

Thanks guys.
I’m about to head back into the garage to pick back up on this. Been a weird couple days at work/quitting my job, lol.

BudW · Mar 11, 2021

!

Sometimes a person has to do just that (for various reasons).

Camtron · Mar 11, 2021

BudW said:
!

Sometimes a person has to do just that (for various reasons).

All for the better. Have a job I start Monday and the owner of the company I just quit, has now reached out for a meeting under the pretext of me taking over his maintenance department. To say the least, I found a flaw in the father/son, manger/foreman team that’s ran his maintenance department for years and, exposed it.

Camtron · Mar 11, 2021

So after installing the new ball joints on the driver side, I can clearly see that the Upper ball joint/control arm is positioned closer to the firewall than the lowers. Should I get the upper lined up with the lower right off the bat?

Sub03 · Mar 11, 2021

Getting the upper ball joint closest to the firewall is really what you want for positive caster.
Not saying this is the correct way

, but this is how I did it:

-Measure ride height. Adjust if needed, take the car for a short trip and measure again. I had to do this several times before I could get consistent measurements. Just bouncing the front between adjustments didn't work for me.

-I set both upper control arms outwards at the front slots an inward at the rear for the most positive caster as possible. Then measure camber. If more negative camber is wanted adjust front slot a tad inwards, if more positive camber is what you want adjust rear slot outwards. When my camber was OK (my goal was -0.5 to -1 degrees) I did the caster measurements.
Now the frustration begins, because caster was uneven between left/right. After several small adjustments (lots of jumping between left/right) I think I found a sweet spot.
Ended up with the following numbers: left camber -0.5, right camber -0.8.
Caster approximately +4.25 left and right.

-Toe was adjusted with tape measure. Set it to 1/8 - 1/16 toe in.

With rebuilt front end, poly pucks and the backyard alignment, I think the old Aspen is handling much better. It really made an improvement. The rear end will be next when the snow here finally disappears.

Camtron · Mar 11, 2021

Thank you, greatly appreciated.

Camtron · Mar 11, 2021

Damnit.
Just broke my pitman arm puller. Suckers on there good.
Gonna get a drink or two in me and get the die grinder out. Figure a little groove cut here and a smack with a 4lb Wilton hammer and chisel there and it will pop right off.

BudW · Mar 11, 2021

Camtron said:
Just broke my pitman arm puller.

Let me guess...made in China?

The upper/lower ball joint relationship changes as the tire goes up (or down) in the suspension arc, on purpose.
This is also why you want the front ride height corrected first.

Wait, you are referring to Caster (uppers more towards the firewall) and not Camber. Disregard what I just said.
BudW

Camtron · Mar 11, 2021

BudW said:
Let me guess...made in China?

The upper/lower ball joint relationship changes as the tire goes up (or down) in the suspension arc, on purpose.
This is also why you want the front ride height corrected first.

Wait, you are referring to Caster (uppers more towards the firewall) and not Camber. Disregard what I just said.
BudW

Probably, was just a cheap OEM brand puller.

Duke5A · Mar 11, 2021

Camtron said:
Damnit.
Just broke my pitman arm puller. Suckers on there good.
Gonna get a drink or two in me and get the die grinder out. Figure a little groove cut here and a smack with a 4lb Wilton hammer and chisel there and it will pop right off.

I seriously wouldn't do that. Your liable to damage gear box pounding away on the sector shaft. Get a good puller.

Camtron · Mar 11, 2021

Duke5A said:
I seriously wouldn't do that. Your liable to damage gear box pounding away on the sector shaft. Get a good puller.

Yea, wasn’t really planning on it. Picking one up tomorrow. More annoyed that my little 5ton posi lock puller can’t get all three jaws on for a clean pull.

Camtron · Mar 12, 2021

Got the pitman arm off with a sweet Taiwanese made pitman arm puller from NAPA and have everything back together finger tight.
Can someone help me out on torque specs?
I was thinking like 135ft lbs for pitman arm nut, no clue for idler arm nut and bolt, 80ft lbs for upper ball joint into control arm, 45ft lbs for ball joint castle nuts and 35ft lbs for tie rod castle nuts.

Steering geometry

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