2WD C10 Modern/Performance Alignments

[moneyeater]

Hello BMERDOC,

thanks for the reply!
My appointment is Thursday at 14.30 German time wich is about 6 hours ahead of your time!
I copied the data from post #68 and hope the alignment shop man can get this right!
I´ll talk to him about what i want and see if it is possible!
Thank you for your help and for the writeup of your knowledge!
Volker

[BMERDOC]

Looks like I was able to get back in time! I hope you see this before you go to the shop. This is an '85 I did last week. Please note that is a picture of the "before adjustment" results. I prefer the right side caster because it is more positive and would like to see the camber in the negative range. Sooo, add as much camber as you can positive caster as you can without adding positive camber (at least keep positive cmber to a minimum). Consider doing the lower control arm modification so that you can gain more positive caster.

[moneyeater]

BMERDOC your the man!!!!!!
Thank you so much for helping me out!
I start of to the shop right now and try to make them do it the way you recommend!
I´ll be right back on the thread when i come back!
Volker

[moneyeater]

Hello BMERDOC,
i´m back from the alignmentshop and so far i´m happy with what they did to my baby although it is not that massive as you recommended!
Here´s a pic of the data!
I hope you can translate it to understand!
Please give me a feedback of what you think!
Sturz = Camber
Nachlauf = Caster
Spur = Toe

[jlsanborn]

Some updates but still miles from an alignment. The LCA shaft mod along with the 2" springs and aftermarket disk brake drop-spindles raised a few issues that I've not completely got sorted out yet. To begin with, the increased caster angle created interference with the upper control arm and the spindle casting. No big thang, just ground a bit off the control arm and casting. Next the lower control arm crashed at the cross member. No big thang, more grinder. Now I'm at the steering stop. The big hunk on the spindle casting that was supposed to ram into the bump-stop/steering-stop bracket thingy now rams into the lower control arm. I started grinding on the casting for clearance but soon realized I'd have to about grind the thing down to like a needle to make it clear. I know the bump stop will be too tall as well, so I'm considering lopping both the big hunk and the bump-stop/steering-stop bracket thingy off and fabbing my own setup. Anyone run into this and come out clean? Would love to hear / see what you did!
I'm also looking for the best way to re-plumb the front brake lines for disk. The OG tab where the hard line transitions to rubber now whacks the upper control arm. I'm sure the hose would be stupid looking anyway if I connected it there. What's the best way out of this?
Thanks for keeping this thread rolling, it's good stuff!

[BMERDOC]

Moneyeayter, looks like they got you on a good start. Especially on the toe and left caster. Consider doing the LCA mod to gain more caster.

jlsanborn, looks like you've had to move some stuff around! On the brake line issue I have seen pics in Delmo's build threads where it looks like he has bent front lines and uses AN bulkhead connectors on the frame to attach his brake hoses. They looked like a good way to do it to me. I think he did it on Nacho.

[kopeck]

Never mind...wrong year.

Sorry

[BMERDOC]

kopeck,
My email notification was waay different than what your post says now. What happened?

[Dano69c10]

Want to do the lca mod;
so is it 1" or 3/4?"

[kopeck]

Originally Posted by BMERDOC

kopeck,
My email notification was waay different than what your post says now. What happened?

I was off topic, my truck's a '79.

For what ever reason it didn't register until after I posted.

Sorry.

K

[BMERDOC]

You weren't off topic. This thread is in the Suspension forum. You can ask anything you want.

[BMERDOC]

Originally Posted by Dano69c10

Want to do the lca mod;
so is it 1" or 3/4?"

Chevyrestoguy did the best thread to date on the caster mod. Here again is the linky...

http://67-72chevytrucks.com/vboard/s...d.php?t=501241

[kopeck]

Originally Posted by BMERDOC

You weren't off topic. This thread is in the Suspension forum. You can ask anything you want.

Oh...I thought this place was only for 67-72 trucks. Seems like everyone gets cranky when things go off topic these days, didn't want to make anyone cross.

Anyway, I just had my '79 C-10 aligned due to uneven tire wear. Before the alignment the truck felt very tight, cornered and tracked well.

Since the alignment it seem to want to wander a bit on corners, you can really feel it on long sweeping ones. It's just unsteady, feels like you are fighting it trying to make a smooth corner. It seems like it tracks pretty straight, but it seems a bit looser over all.

They sheet shows they used '82 specs, not '79...not sure if that's part of the issue or not. I know these square bodies are all pretty similar...

This is how they left it with the '82 specs:

Caster (1.6 - 2.6 deg):

Left 1.9
Right 2.6

Camber (.2 - 1.2 deg):

Left .7
Right .5

Toe (.15 - .25 deg):

Left .20
Right .20

Thanks,

K

[BMERDOC]

Don't worry about the 67-72 thing. You are fine where you are. I'd love to know what your "before" measurements were.

I think we have established that 1/16" toe per side and 1/8" total toe is good. 1/16th is equal to .14' (minutes) or .25°. Your .20° is fine. I think your problem is from the caster and camber.

Because the right is 2.6 and the left is 1.9 your truck should want to drift right. The fact that the angle is so shallow kills the stability or as you put it, it would tend to wander and not track tue without a lot of corrections.
This is why we want to either push the lower ball joint forward or the upper back (or a little of both) to increase positive caster.

Your camber is positive which means that the top of the tire is already tipped towards the outside which would kill confidence in the turns. To get a better idea of where you were and where you are now can you post your before angles? In what way were your tires wearing to make you want to get an alignment?

[kopeck]

One tire (I think the passenger, I would have to double check) was wearing pretty hard on the out side, the driver side had bit of wear on the inside but nothing to extreme.

Here's the initials:

Caster:

Left 1.5
Right 2.6

Camber:

Left .3
Right .5

Toe:

Left .05
Right .15
Total .20

All in degrees.

Thanks,

K

[Dano69c10]

Originally Posted by BMERDOC

Chevyrestoguy did the best thread to date on the caster mod. Here again is the linky...

http://67-72chevytrucks.com/vboard/s...d.php?t=501241

Thanx for the link. I could not find it. I thought it was by Rob or Bmerdoc.
Dano

[BMERDOC]

It looks like they only added a shim to the front of the left side and adjusted toe. It pushed the caster back to 1.9° but pushed the camber out to .7°.

If I had to take an educated guess I'd say that the excessive positive camber is not helping you in the turns. Your tire wear with the new toe adjustment may be affecting it also. A tire that is settled into a wear pattern can cause ill handling vehicle and can be aggravated when the angles are changed. They didn't move the alignment around too much so I'm not sure how you can feel so much of a change.

Do you know if they checked the the suspension, steering and steering box for tightness?

[kopeck]

Well, I stopped in to the shop and told them about the change in handling and they didn't seem all that interested in helping me out. They did say they would take to for a drive on Friday but that was about it. I got the "well, it's an old truck and they don't handle like new vehicles" line as well.

He thinks it's something in the rear that's causing the trouble. I do have a broken leaf in the back, it's been that way for a long, long time. I have a feeling they're going to point to that and say "see, nothing wrong up front, you need new leaf springs".

I should mention that my steering wheel is also way off now, going straight it's a good 1/8 turn off center or more.

K

[BMERDOC]

I have to admit I'm at somewhat of a lose as to what changed in your truck so much during the alignment that you can feel such a big difference.

You mentioned that your steering wheel is not centered now. That tells me that they didn't lock it down when they adjusted toe so I'm kinda skeptical of the accuracy of the numbers. I do recommend that you at least change out the broken spring pack. I think you should take it upon yourself to check the tightness of your front suspension, steering and steering box. Also check the tire pressures to make sure they are correct. I would also recommend taking it to another shop for your next alignment.
I have steered clear of telling you about maxing positive caster and negative camber because you were trying to diagnose a problem and you found us on the Internet (thanx, BTW). But for the sake of the thread and your desire to have a better handling truck I would suggest that you skim through the thread and decide for yourself if you'd like to go a tad further to make it handle better. I have to go back and reread some of the stuff myself. Depending on how far you want to go a better alignment is all you may need. One of the simplest rules I have found so far is that without modifying the suspension the best thing you can do is remove all the shims (I'm not sure how big your shim stacks are) and perform the alignment to add or equalize the caster and then set toe. On a stock height truck removing all the shims still didn't move the camber negative enough to get it where it needed to be so adding shims to adjust it would only hurt things.

[kopeck]

Honestly, the place I usually take my cars/trucks to get aligned has an awesome reputation. The issue is it's a bit of a hike from my house/work where the place I took my C-10 this time was convenient. I had trouble with them aligning my Golf a number of years ago, I chalked that up to as a one time deal, maybe it wasn't.

The first response I got when I walked in was "the alignment sheet doesn't lie", no where in there was a "huh, well lets see what we can do to help you out".

Before I brought the truck in greased all the suspension stuff and looked it over pretty well. I tugged on the tire and didn't find any play in any of the tie rods but I can do it again.

I know I should change out the spring pack, it's been broken since I inherited the truck and that's over 12 years ago now. It's never bothered so I just ignored it. It's heavy half so there's a little more heft there to begin with.

Thanks for your time, it did seem odd that things felt so different after what looked to me like minor changes...

K

[BMERDOC]

"The alignment sheet doesn't lie" huh? Doesn't sound like they wanna keep customers. The alignment doesn't lie either. The simple fact that the steering wheel isn't straight is cause for a free redo of the alignment (at least at MY shop it would be). I don't know that I'd want them doing another one on it anyway. When you get time have your usual shop do it and see if that changes anything. Let us know what you find out.

Hang around the site too!! There is room for you here. There are plenty of guys on the Square body side that love to talk trucks! Welcome to the forum!

[kopeck]

Guess, what?

I rotated the tires and the problem went away. Not only that but my steering wheel is straight again.

That one tire really must have been pullingt the truck hard. Our road are pitched a lot, typically you are always driving "up hill", I had to steer "down hill" to keep it straight.

So the alignment guys were probably right but he could have approached it differently. I think I'll stick with my usual guy.

Thanks,

K

[BMERDOC]

We refer to that as a tire pull. Good job finding it!
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[kopeck]

There shouldn't be any problem running those on the back is there?

I need new tires but it's a fair weather truck so I would like to get as much life out of these things as I can...

K

[BMERDOC]

For the most part, rotating tires to get rid of a tire pull is harmless. If its just a bad wear pattern you shouldn't have a problem. If its because the cords are seperating it may come apart and it better for it to be on the rear.