2WD C10 Modern/Performance Alignments

[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

[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.

[502ms]

Great info. So, for a bagged truck, alignments are done at stock/ operational ride height, correct?
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[BMERDOC]

Yeah, I think you'd wanna do the alignment at the ride height its gonna be driven at most. I'd love to get a bagged truck on the rack to see what happens to the alignment as the truck is raised and lowered.

[502ms]

Originally Posted by BMERDOC

Yeah, I think you'd wanna do the alignment at the ride height its gonna be driven at most. I'd love to get a bagged truck on the rack to see what happens to the alignment as the truck is raised and lowered.

Thanks! Too bad you are so far away
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[jjzepplin]

Subscribed

[RdoubleU]

First off : Major Thanks to BMERDOC for starting and supporting this thread

Wanted to share my experience and results from using this thread as a solid guideline for aligning my '68 C10

Here's a summary of this threads research (correct me if I'm outta line anywhere so I don't misinform someone else.)

[RdoubleU]

For my truck I was able to achieve the below specs

• Camber .3*+
• Caster 6*+
• Toe In .1*

Unfortunately I was unable to go negative Camber on the passenger side due to limitations of the stock crossmember on my truck. They were able to get the driver side negative. They fully removed all shims on the passenger side and milled the factory shim down to its least amount while still maintaining its integrity but could only achieve .3* on the passenger side. So I chose to have each side equal the .3*

For the impressive Caster numbers it was due to me investing in Porterbuilt's (Nate) Forward Arm series. And I am very very happy with this decision and the result it produced: http://67-72chevytrucks.com/vboard/s...d.php?t=537266

The truck tracks straight has good road feel now and is also very confident in its driving characteristics

Thanks again for the info in this thread, hope it helps someone else out as well

[BMERDOC]

Well done! Nice chart! Very easy to read and understand. My toe specs were in minutes and not degrees so I'm concerned they may have confused degrees and minutes. I'm starting to prefer fractional toe specs for ease of memory. 1/8" toe in, 0 or 1/8" toe out. These are TOTAL toe specs (1/16" per side). 1/8" toe in and 0 for stock and most modified trucks and 1/8" toe out for Corner Carvers. I'm not sure how much undesireable wear comes from the 1/8" toe out so I'd stick with 1/8" toe in or 0 for most trucks.

Its a shame about that camber. It woulda been nice to get it negative but at least its still in stock specs which doesnt raise any concern. Are you running any kind of drop springs? IIRC, 3" drop springs dropped the camber into a nice zone with no shims needed (before evening side to side).

I see the Porterbuilt Forward Arm Series control arms worked out nicely for you. I have a list of stuff I'd like to order from Nate and his family myself!

Enjoy your improvements!! Post up some pics!!

[BMERDOC]

Ok Kids! I did a final alignment on my truck. I will continue with modifications but this is as good as it gets right now. Minimal shims, maximum angles. I started a different thread for that single alignment so that others could find it. Heres the linky...

http://67-72chevytrucks.com/vboard/s...d.php?t=582187

[Street Smart]

Great thread guys! Thanks for all the real world specs!

[BMERDOC]

Originally Posted by Street Smart

Great thread guys! Thanks for all the real world specs!

Glad you found the info useful! I'll be updating as soon as I get a double adjustable Panhard Bar and the Caster Mod done.

[LEEVON]

Unfortunately I was never able to get my alignment where I wanted it before I had my own shop (which is recent). My best tech and I were able to tinker on our own time and get it where we wanted.

The truck just got all new front suspension with 2.5" spindles and Moog 6454 HD springs cut exactly 1 coil. Rear suspension is 4" springs and 1.5" blocks, with a double-adjustable panhard bar. With this combo, the a-arms are slightly above level, the tie rods nearly level and the upper ball joints are at an acceptable angle.

Thrust Angle: .13 (no change required)
Camber: -.50 to -.53
Caster: 2.7 to 3.2
Toe: .08 toe

Sorry, forgot the printout. Rides perfect though!

[BMERDOC]

Leevon, Did you see my thread about "Match using Cross specs"? It looks like you have one of the latest Hunter machines and it should have that feature. You can find it in my sig as "Easiest Alignment Ever". Any shimmed vehicle can be aligned like this. Its so quick and easy. .13 for a thrust angle is great. I think mine is near .25. I'm sure I'll mess with it once I install my double adjustable bar on. The only I would be concerned about is getting the trailing arm bushings in a bind. There are so many mods that I want to do but I've been concentrating on aesthetics recently.

[BMERDOC]

For you guys paying attention I wanted to share a thread that 19GM71 posted. Its another great mod to get your steering and suspension done. I priced out this set up for my truck and I think it came out to about $85. Totally worth it!

http://67-72chevytrucks.com/vboard/s...d.php?t=620584