The Stovebolt Site Forums The Shop Area Driveline Front End Alignment Process '69 C-10

The Green Farmer is a '69 C-10 Stepside, bare bones, 6cyl, no power nothing. Before this, it drove just fine, straight down the road (but tons of slop in the system, hence the need for a rebuild), and returned to straight after turns.

I just had the front end rebuilt (all new control arm bushings, ball joints and tie rod ends) and had them add a power steering kit (not sure which kit yet, basically a stock pump and rebuilt box). The numbskulls at the local Firestone (where the shop took it for alignment) sent it back in undriveable condition. If you took your eye off the road for a nanosecond, you'd veer one way or another. A slight move of the wheel resulted in the truck taking off in that direction even more than commanded. Nearly hit a curb in the 200yds I went before returning it to the shop. I can't believe anyone test drove this and thought that was acceptable, but they did. I recognized this was some combination of negative caster or toe out.The alignment sheets they sent verified almost zero caster.

I've searched the interwebs and here but haven't found conclusive procedure (order of what to do first) on setting the alignment. My summary of what I find combined with my (feeble) brain and knowledge of geometry is:

Truck on level ground, check and adjust ride height as needed.
Set Camber
Set Caster
Set Toe
Recheck all of the above.


To adjust camber, add shims both front and rear of the top control arm for adding (more positive) camber, fewer for reducing (more negative). If you have removed the last shim and still not in spec, can add to the lower arm as needed.

To adjust caster, add shims in front and none (or remove) in rear to add positive caster, opposite for reducing caster.


Am I missing something?


As an aside, spoke with the Firestone manager who stated when adjusting the camber caster that whatever you did to the front shims you had to do to the rear - pretty sure that identified my problem right there, no?

If after you get it to alignment specs and it is still twitchy check to see if the power steering pump and gear box are a match. A 1300psi GM pump will make an 850psi Ford box write horror stories. Also check to see if the monkeys used a quick ratio steering box off of something like a Trans Am rather than a passenger car/truck box. One is around 16:1 while the other is around 24:1--- big difference.

Your problem is in your first few sentences- - - -"Firestone"! I do warranty and damage claim inspections, and a huge number of my assignments involve claims against Bridgestone/Firestone stores. Find an old established independent alignment shop with someone there who knows enough about alignment theory to make your truck steer properly. Who did the installation of the new components? There are several possible ways to assemble things improperly that can cause the symptoms you're describing, but an experienced front end man should be able to spot that kind of thing right away. BTW, the "manager" (who is actually a salesman) is right about the camber adjustment procedure. That's the way I taught it for over 30 years.
Jerry

Hotrod,

Re your BTW, blunder on my part, (now corrected). I meant to say CASTER. Agreed that for camber you adjust both, but not caster. Correct me if I’m wrong this time.

Nope, you've got it right there. To make a caster adjustment without affecting camber, take a shim out of one end, and install it in the other, like moving a shim from front to rear, or vice versa. The tip about checking on which steering gear was used is also a good one- - - -some of those Saginaw boxes have a tall center tooth on the sector gear that gives a very fast response as the wheel is moved off center, and a slower rate as the limits of travel are approached. If the center point of the steering gear is not adjusted properly, there will be some slack when the vehicle is traveling straight ahead and you'll have to "herd" the truck down the road. Finding the center point and adjusting the sector preload for a zero-clearance situation while driving straight ahead is the very first thing to do during a top-quality wheel alignment job. With most of today's vehicles having rack and pinion steering, a lot of so-called "alignment" guys have no clue how to do that!
Jerry

As noted above, Definitely check the power steering pump and steering box for compatibility. If the shop used true stock components then that is probably not the issue.

Also, I once had a vehicle with wider than stock front tires, when it was time to put on new tires I went with a more stock size tire in the front which had a very dramatic affect on steering, ie... I didn't have to "armstrong" the steering wheel anymore>