positive camber

[chevroletrestoguy]

Guys-
It's been forever since I posted. Thank goodness I found my password written down somewhere or this profile was probably toast!

Originally in around 09 when I put this truck together, I used POL tubular upper and lower control arms. Trying to remember I think I used 2.5" drop spindles and maybe one" drop springs with disk brakes. I remember it dropped the front lower than I wanted and I think I replaced the drop springs with no drop. So I raised it 1". The rear has 3" drop. I like the stance now.

SO..... With the POL tubular arms, I had excess positive camber and you know with these trucks, that gives you no room to work with as far as shims goes. I've put maybe 1200 miles on the truck since 2017 when I got it on the road and the outside of the front tires were wearing considerably.

So I just completed a changeover to CPP tubular control arms. I think this may have helped some, but I'm still kind of surprised at how little. What else could be causing this? Could the spindle or Springs be causing it? I haven't had it realigned yet, but I would curious why this is happening...

[MySons68C20]

How are you measuring this or just eyeballing? I think getting it aligned after the change would be a good start.
I don't have the link but there are threads regarding alignment numbers on this site that work well with modern tires.
That is a very pretty truck!!!

[chevroletrestoguy]

Originally Posted by MySons68C20

How are you measuring this or just eyeballing? I think getting it aligned after the change would be a good start.
I don't have the link but there are threads regarding alignment numbers on this site that work well with modern tires.
That is a very pretty truck!!!

At this point, mainly eyeballing it, but I've also used a level. I appreciate that!

[theastronaut]

Check the studs where the upper control arms bolt on- are there thick spacers that could be ground or machined down to move the upper arms inward? I think squarebodies have thicker spacers than 60-72 crossmembers had, and it's common for squarebody crossmembers to be swapped in.

If it doesn't have thick spacers, with that mild of a drop you could go back to standard height spindles and 3-4" drop springs to change the angle of the A-arms which would give you more negative camber.

It's also possible that the upper arms are made longer to get rid of the thick stack of shims that most trucks have.

My '66 is slightly lower, it has stock arms and crossmember, CPP spindles, stock springs with one coil cut off, and without any shims it has about -1.5* camber.

[chevroletrestoguy]

Originally Posted by theastronaut

Check the studs where the upper control arms bolt on- are there thick spacers that could be ground or machined down to move the upper arms inward? I think squarebodies have thicker spacers than 60-72 crossmembers had, and it's common for squarebody crossmembers to be swapped in.

If it doesn't have thick spacers, with that mild of a drop you could go back to standard height spindles and 3-4" drop springs to change the angle of the A-arms which would give you more negative camber.

It's also possible that the upper arms are made longer to get rid of the thick stack of shims that most trucks have.

My '66 is slightly lower, it has stock arms and crossmember, CPP spindles, stock springs with one coil cut off, and without any shims it has about -1.5* camber.

All of this makes sense to me. The frame is from a 63. The spacers are fairly thick and I suppose that they could be ground down. But the cross shafts are probably close to hitting on the edges and the center of the bracket at this point already. I was thinking going back to stock spindles and using maybe 3 inch drop springs might help give me more negative camber. However, first of all I plan to get it aligned to see how bad (or not bad) this really is. I just know that there has to be some more adjustability in this somewhere that I am missing out on and I think you may have hit on exactly what that issue is.

[Richard]

Personally I would figure out why you cannot adjust to correct camber with the stock height springs and drop spindles. It is the best option IMO. From my experience if you do the 3" drop spring your problem will just be reversed, excess inner tire wear. The SLA (short/long arm) suspension camber curve accelerates the deeper it gets into the cycle. A 3" drop spring will put the static position of arms deep into the camber curve cycle causing accelerated inner tire wear even if the suspension is aligned. I lived with changing my front tires every 10-15k while I had the drop springs in it. Yes, my truck had stock camber and slightly increased caster at ride height.

[chevroletrestoguy]

Originally Posted by Richard

Personally I would figure out why you cannot adjust to correct camber with the stock height springs and drop spindles. It is the best option IMO. From my experience if you do the 3" drop spring your problem will just be reversed, excess inner tire wear. The SLA (short/long arm) suspension camber curve accelerates the deeper it gets into the cycle. A 3" drop spring will put the static position of arms deep into the camber curve cycle causing accelerated inner tire wear even if the suspension is aligned. I lived with changing my front tires every 10-15k while I had the drop springs in it. Yes, my truck had stock camber and slightly increased caster at ride height.

Yeah. It's a head scratcher for me. At this point, I'm assuming that the tubular A arms have additional geometry built into them to correct the reverse condition that you mentioned, negative camber and having to use too many shims.

[chevroletrestoguy]

I'm thinking that I'll clearance these two spots on each side. That should buy me enough clearance I think.

[Richard]

Originally Posted by chevroletrestoguy

Yeah. It's a head scratcher for me. At this point, I'm assuming that the tubular A arms have additional geometry built into them to correct the reverse condition that you mentioned, negative camber and having to use too many shims.

A longer upper arm or shorter lower arm will not really change the camber curve. Just will allow using less shims with a drop spring. With a drop spring the top of tire pulls in quicker as you are deeper into the curve. What you are thinking may be good? IDK? Maybe, if I was in your situation and wanted to still use the aftermarket arms I might pull the uppers and shorten them 1/4"-3/8". When altered from stock it is hard to have everything be just bolt-in.

[lolife99]

Post some pics of your suspension.
Any chance the upper control arms are on the wrong sides?

[chevroletrestoguy]

Originally Posted by lolife99

Post some pics of your suspension.
Any chance the upper control arms are on the wrong sides?

I had POL tubular arms on it circa 2009 edition and I always wondered if that were the case because they did a horrible job of marking them/showing anything online at that time. But I did have them on right. Now, I've changed them to CPP arms and I'm sure they are on correctly and while my situation is better, it's not as good as I had hoped. I'm pretty sure I've achieved negative camber on the passenger side, but the driver side is pretty iffy.

[pjmoreland]

If you had some room between the cross shafts and the cross member brackets, then these spacers that are thinner than stock would help.

https://www.performanceonline.com/19...-Control-Arms/

[chevroletrestoguy]

Originally Posted by pjmoreland

If you had some room between the cross shafts and the cross member brackets, then these spacers that are thinner than stock would help.

https://www.performanceonline.com/19...-Control-Arms/

I've already removed the factory spacers that those replace. I don't have anything in there except knurled spacer that holds the stud in place.

[cwcarpenter98]

Double check the upper arms are on the correct side. The previous owner reinstalled mine on the wrong sides, so the truck had way too much positive camber. I only found out after doing the caster mod and couldn't get the truck aligned properly. Switched the arms back to the correct side and problem solved