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Old 06-17-2013, 02:23 AM   #1
BR3W CITY
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Front Susp/Alignment issue

So I'm down to the fact that my front suspension is now the weak point on my truck, and I'm trying to figure out exactly why. Its the only part of the truck the p.o setup that I haven't changed ALL of yet.

Setup; 66 c10 w/ 71-72 style control arms (metal bushing), what look to be drop spindles (unknown) and unknown springs. It does have a decent front sway bar. Seems likebunch of shims on the lower control arms. a Power steering off the same 72 donor. I just added new qa1 DS304 shocks. Total drop is about 5" from what I can tell. The front tires are 235/70/15, which I feel is actually too tall, and are my spare non-slick rear tires. The old tire size I've run was a 235/60/15..a little harder to find.

Pics for height reference (on the larger tire)




Problems;
1. Its always been a bit floaty, but I can expect that from a heavy old lowered truck, with higher sidewalls. The new shocks have improved some of the roll and floatiness.
2. When switching lanes, its very sudden, so when it crosses the groove into the next lane it can be twitchy. This makes is tricky to drive on uneven lanes in construction or similar circumstance.
3. The power steering feels a bit overboosted, both when I had the old engine and sbc p/s pump, and my current lq4 with the hydroboost setup.
4. even at low speed turning, like a uturn or egressing a driveway, the front tires squeal a bit. You can feel the feedback in the wheel, like the front wheel s are fighting each other or tripping over themselves. I really want to fix this so I don't ruin tires. When you look at the tire wear, it does not show "strips" like too much caster or camber would from what I've seen. The tires show sort of a "clawing" outward on the tread. Maybe as if there was way too much toe?

5.there is about 1/2 turn difference on right and left lock. I imagine this just is a result of the pitman arm having been attatched a spline off at some point.


I really appreciate the input, its one of the last things I really need to do to transform the feel.
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Last edited by BR3W CITY; 06-17-2013 at 07:10 PM.
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Old 06-17-2013, 09:41 AM   #2
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Re: Front Susp/Alignment issue

First off have you had the front end aligned yet? If so what are the specs? Also you mention shims on the lower a-arms I didn't know there were any place for shims or adjustment on the lowers so maybe you mean upper?
You will want as much caster as can get dialed in on these trucks, this will also help that "overboosted" feel some. There are threads on the mod to improve the caster, I ended up getting aftermarket upper a-arms that got me about 7-8 degrees plus I needed the clearance for my coil over swap I had done. When I got mine redone it did help on the areas you are talking about. There is a good thread or two on alignment on here but I would start there.
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Old 06-17-2013, 02:33 PM   #3
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Re: Front Susp/Alignment issue

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Originally Posted by Custom 68 View Post
First off have you had the front end aligned yet? If so what are the specs? Also you mention shims on the lower a-arms I didn't know there were any place for shims or adjustment on the lowers so maybe you mean upper?
You will want as much caster as can get dialed in on these trucks, this will also help that "overboosted" feel some. There are threads on the mod to improve the caster, I ended up getting aftermarket upper a-arms that got me about 7-8 degrees plus I needed the clearance for my coil over swap I had done. When I got mine redone it did help on the areas you are talking about. There is a good thread or two on alignment on here but I would start there.
Haha ya I meant upper c/a, I was lying on my back while looking at it lfmao.
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Old 06-18-2013, 09:24 AM   #4
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Re: Front Susp/Alignment issue

Check that you don't have any worn parts, make sure wheel bearings are packed and properly adjusted and take it to get an alignment.
Thats what you need to do first.

Only Camber and Toe wear tires. Caster does not cause tire wear.

Moog makes an offset upper control arm shaft that will reduce the amount of shims.

It looks like the pass. side tire/wheel is set back further in the wheel well than the driver side. Is that from camera angle or is your wheelbase really shorter on that side?
May want to have someone follow behind you and see if truck is tracking straight down the road.
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Old 06-18-2013, 11:26 AM   #5
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Re: Front Susp/Alignment issue

^Pictures were from two seperate locations and the passenger side shot had the wheel "cocked" just slightly.

I had replaced the shocks and the rag joint, and the truck track very straight down the road. I can no-hands for about 15-20 seconds, which is pretty dang good on the 3rd world road conditions of Wisconsin.

It was aligned a while back, but not with these shocks. I can gladly do that, but was hoping to clear out any glaring issues before going over there. The shims on the control arm strike me as weird, but then again the last few cars I've worked on had slotted alignment plates.
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Old 06-19-2013, 12:20 AM   #6
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Re: Front Susp/Alignment issue

The shocks won't effect anything as far as wheel alignment.
The pitman arm and sector shaft have an index on the spline and will only go together in one spot.
The tire squeal could be caused by many things like low tire pressure, worn parts, front end alignment to name a few.
These are 40+ year old trucks that were designed with bias ply or nylon tires. Now days we use radial ply tires on them but even on a perfect day they will never drive and handle like a modern truck
If everything is tight and nothing looks bent I would say you are good to go. Make sure its aligned and watch your tire wear for problems.
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Old 06-19-2013, 12:36 AM   #7
BR3W CITY
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Re: Front Susp/Alignment issue

Quote:
Originally Posted by wraprail View Post
The shocks won't effect anything as far as wheel alignment.
The pitman arm and sector shaft have an index on the spline and will only go together in one spot.
The tire squeal could be caused by many things like low tire pressure, worn parts, front end alignment to name a few.
These are 40+ year old trucks that were designed with bias ply or nylon tires. Now days we use radial ply tires on them but even on a perfect day they will never drive and handle like a modern truck
If everything is tight and nothing looks bent I would say you are good to go. Make sure its aligned and watch your tire wear for problems.
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Thanks for your input. Tire pressure was checked when I re assmebled everything with the shocks and rag joint etc, so thats all accounted for. Ball joints look good, I don't feel any play in the tie rods (truck on the ground).

Are you familiar with the possibility of the center link being on backwards? This was mentioned to me as a reason why I have a 1/2 turn extra to one side. Apparently it can be flipped over and put back incorrectly? I hadn't heard that one before, but considering some of the thigns the P.o. did, maybe it shouldn't surprise me.
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Old 06-19-2013, 08:48 AM   #8
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Re: Front Susp/Alignment issue

Quote:
This was mentioned to me as a reason why I have a 1/2 turn extra to one side.
Isn't that from the PS conversion? The box is now offset by 1/2 inch. This causes the pitman and idler arm to no longer be parallel.
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