2WD C10 Modern/Performance Alignments

[BMERDOC]

I wouldn't go stacking shims to get a lot of camber. If you read through the thread you'll notice I am very anti-shim. They should only be used to tweak angles for final dial in. If its camber you want you'll need to look up the Caster Mod. It is a little work but will get you 6 to 7 degrees of Caster. Best low buck way to do it and I'll wager that if you are a patient man you wouldn't even have to take the lower arms out of the truck to get it done.

[picklito]

Originally Posted by BMERDOC

I wouldn't go stacking shims to get a lot of camber...

Thanks! Don't need more camber. Want to angle the upper arm back a bit to add caster, until I do the full lower cross shaft relocation. Just wondering about trying a temporary "improvement" until I do the whole front end. Still have a few weeks before that.

[BMERDOC]

Sorry. I meant caster not camber. I'd just wait until you modify the lower shafts. How are you adjusting toe? Are you using any kind of gauge for caster/camber?

[picklito]

Thought that's what you meant!

Very primitively (we do what we can, right?): Tape measure and Ms. Picklito for toe. Bubble level for camber. Caster is actually an old measurement when I had it on a rack, but I "shouldn't have" changed that much since I haven't yet changed the front/back shim differential?? Truck is working well except for almost ZERO return-to-center and feeling like I'm constantly trying to find "straight" on the freeway. Not darting around, not dangerous, just no sense of center.

Mine looks like I could only move the lowers forward about 1/2" or less without significant grinding, but it will be easier to tell once parts are on the bench. I may "bail" and just go with the 1/4" replacement shafts.

[BMERDOC]

Well I guess my question would be How thick are those shims? You should do ok if you remove the rear shims and just leave the front ones in but you won't get the caster you desire for more straight line stability and return-to-center. If you look at my Easiest Alignment Ever thread I wasn't even able to gain 3.0° caster with no shims and my steering is still lacking. Its the best its ever been but its still dead. I don't think any noticeable improvement will be made until the caster is +5°.

I've heard of people not being able to gain the full 3/4 inch needed to gain the 6 or 7 degrees. The most many could muster is 5/8" but still no one has been able to verify the gains at each increment (that I've seen anyway). I just got a new pair of jackstands from HF to start on the next phase of my project (gotta do it in the driveway, my workplace is a construction nightmare at the moment) and that will include the Caster Mod. I think I'll drill locating holes at 1/2", 5/8" and 3/4" at 90° intervals to test each caster gain so people will have the info. Hopefully my driveway work will go over relatively quickly so I can align it and announce my findings.

[picklito]

That would be a pretty cool experiment, and a lot of people would benefit from your hard and greasy work. It is a little odd that we all have so much different in clearance at the lower rear cross shaft. I'm also keeping my eyes open for someone who posts what they can get with just the aftermarket shaft. Maybe that will be me.

[BMERDOC]

On a quick note because Im out with the girl. Which shafts are you referring to? I bought some a while ago because of a thread and mine turned out to be stock. Lets compare notes.

[picklito]

I'm referring to the lower control arm cross shafts, that many are reporting come with the locating holes already moved 1/4".

[BMERDOC]

I had to look back to find it (post 155). I bought a pair. Raybestos 595-1017. When they got here they were 1017B. I didn't send them back because I got them at such a good price ($20ea I think) The 1017B is the Service grade whereas the 1017 is the Professional grade so I still can't verify they were all drilled like that. If you get a set let me know what you find out.

[picklito]

I'm planning to order the Mevotech MK6147 mentioned elsewhere, since they're supposed to have the 1/4" already done. And I'm 'assuming' that mine are the originals, but I have no way to know that. Do we have a spec for where the "stock" holes are and where the "1/4" holes are?

[BMERDOC]

The crossshafts are located by pins in the front of the crossmember. If you look at the last picture I posted you'll see that the locating hole is 1.25" away from the front. The ones that are an additional 1/4" would have a locating hole measurement of 1.5" from the end. If it was drilled for the 3/4" locating hole it would be 2" from the end.

[picklito]

well that was easy! I'll post the hole location once mine arrive.

[BMERDOC]

A few points to ponder:

I looked up that 6147 number and found that several manufacturers use it. One being Moog in their Problem Solver line. Could it be that any cross shaft with the number 6147 has the index drilled at 1.5"? I think its completely plausible.

Crakajax crunched the numbers and found that for every .25" of movement a gain of 1.4 degrees is gained. So as an example:

My truck currently is 2.7 on the left side. Just replacing the shaft with the 6147 number should net me 4.1 degrees which isn't bad. If I drill the index at 1 7/8" (1/8" equals .7) my caster would be at 6.2 and at the 2" mark my caster would be at 6.9 degrees.

[SCOTI]

Originally Posted by BMERDOC

A few points to ponder:

I looked up that 6147 number and found that several manufacturers use it. One being Moog in their Problem Solver line. Could it be that any cross shaft with the number 6147 has the index drilled at 1.5"? I think its completely plausible.

Crakajax crunched the numbers and found that for every .25" of movement a gain of 1.4 degrees is gained. So as an example:

My truck currently is 2.7 on the left side. Just replacing the shaft with the 6147 number should net me 4.1 degrees which isn't bad. If I drill the index at 1 7/8" (1/8" equals .7) my caster would be at 6.2 and at the 2" mark my caster would be at 6.9 degrees.

I can measure the Moog Problem Solver shafts that I recently purchased & compare them to my OE shafts that were removed.

[BMERDOC]

That would be awesome Scoti! I'm thinking the other lines could be re-boxed Moog parts or another supplier altogether making these parts for everyone.

[SCOTI]

Originally Posted by BMERDOC

That would be awesome Scoti! I'm thinking the other lines could be re-boxed Moog parts or another supplier altogether making these parts for everyone.

For what it's worth.... We redrilled the new shafts .750" & I was able to install the arms w/minor trimming to the bushing flange area & x-member. I'll measure them tonight for reference info.

[BMERDOC]

So you drilled them at a two inch centerline from the end? What did you use to drill?

[Domer]

Here are my measurements for everything I did to my lca.
7/16-20 x 1.25" Allen hex bolt
Stover lock nut and locktite

Head dia. - .650"
Drill - .653"

Drill at 3/4" offset

First hole at .9515" from shaft edge.

Distance - 9.0625" c-c of holes

7/16" drill bit for xmember

[picklito]

SCOTI: Looking forward to your numbers. Especially if you can compare Moog and OE pieces.

Domer: To clarify your numbers, are you saying that your stock hole was .9515" from the shaft edge and you moved it an additional .75"?

BMERDOC: That 6147 number has caught my attention, too. I'm sure lots of these "brand names" are just re-boxers cuz it's doubtful there are that many factories cranking out shaft kits for old trucks, right? But Moog claims "made in U.S.A." and I just assumed the others like Mevotech would be Chinese. Anybody know?

[Domer]

Negative, those were the measurements for the new front hole then went the 9.0625 for the next hole. I used a regular drill bit, but ground the flutes down shallow so the bolt would fit good. If your using the factory pins the hole doesn't need to very deep.
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[picklito]

Sorry Domer, I'm still confused. If your new hole is .9515" from shaft edge, this seems very far from the 2" from edge others are using... or... is it the other hole 9.0625" away that lands 2" from the shaft edge?

[Domer]

Now I can't remember.. Crap.. I'll have to check. I won't be home for a couple of weeks..
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[SCOTI]

Pics as promised.

First pic is of the original OE shaft as removed from the arm. The dimension I'm reading for the divot C/L is ~ 1.5" from the end of the shaft....

[SCOTI]

Next up is the re-drilled replacement Moog K6147 shaft.

It appears the 1/4" difference is the opposite way we would want it to go for caster w/it's ~1.25" C/L. It does answer why I was able to trim a minimal-moderate amount of material to get them to clear vs others possibly modifying their originals (or replacements that utilize the OE dimensions).

The problem w/trying to answer certain questions sometimes is it creates additional questions . . .....

[BMERDOC]

Hmmm. Well my Raybestos measure at the same centerline. I was hoping someone out there had the forethought to dial in a bit more Caster on replacement parts. I guess not. I'm taking the front suspension off my 67 in the next couple of days for some cleaning and painting, a disc brake swap, and the caster mod. I'll look over the cross shaft when I have them in my hands. I think I'm gonna have the machine shop drill at 2" and 1 7/8" at 90° apart to compare numbers on the rack. I think its be cool to machine a diagonal line into the shaft and a couple of flats for a big wrench for adjustment of caster. Just thinking out loud.