1992 D350 Cummins 2wd pickup tire scrub

Hello all.
I just replaced all the front end parts on my brother's truck (used the same control arms but new bushings and new ball joints).
It is a '92 Dodge D350 2wd truck with a cummins in it.
The list of parts replaced is as follows:
-Upper ball joints -Lower Ball joints -inner tie rod ends -outer tie rod ends -control arm bushings upper and lower -drag link -idler arm -new shocks
I tried to put the adjustments back as close to where they were when I took the thing apart. When I first backed the truck out of the garage and turned the wheels all the way, the outside edge of the wheel wanted to dig a trench in the yard.. I figured it was just improper alignment. I took it to the alignment shop and "supposedly" they aligned the truck and had no problems, but when I turn the wheel all the way in either direction, the wheels literally are scrubbing the tread off the tires super quickly. In fact, the steering now binds to the point that the truck will stop when you have the wheel at full lock. Driving in a straight line, the truck wants to pull to the right and has some severe bumpsteer. It was easier to drive the thing and the tires wore less before I did anything to the truck! I am puzzled as to what is wrong if the alignment is "proper"..
I figured since the tires are a bit cupped from running about 10,000 miles with worn ball joints, the outside edges of the tires were just trying to catch up to the inside, but that does not really explain the tire scrub.
Any ideas would really be appreciated. I am wishing I hadn't done anything to the truck now..
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It's amazing nobody else has ever had this problem!
Well, you people are lucky! LOL!
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Do a google search using "ackerman effect". The factory uses the same front end parts on trucks with different wheelbases but the steering geometry is correct at only one specific wheelbase. I have driven GM long wheelbase (long bed crew cab) pickups that scrub so bad on a tight turn that they won't move forward on solid ground until the steering wheel is moved toward center.
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While thats true, the OP is looking for a reason that the truck now behaves differently. This also does not explain the pull to one side or another. IMO, he needs to find a better alignment shop, since going in a straight line the truck should not be subject to any geometry influences.
--
Max

"Everyone is entitled to his own opinion, he is not entitled to his own
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Well, I figured it out today. Boy, do I feel like a dumbass!
I somehow got confused and installed the drag link backward.
I laid on the ground this afternoon and looked at it for a long time... Fortunately, I had taken a couple of pictures of the parts laying on the floor.. I remembered the tie rod ends were at a ninety degree angle to each other when I removed the old link... with the drag link backward, the tie rod ends were in the same plane... i gently removed the parts and re-oriented the drag link. The mofo is golden now. No scrubbing of tires, no binding.
Honestly, I haven't ever seen a suspension that would work with the parts in backward. The alignment guy must not do enough of this type of front end to notice the difference. It "looked" right. Now it feels right. I am so glad!
Thanks for your responses. I learned about the ackerman effect, which is ultimately what led me to realise my error of installation. I'm just glad I didn't ruin the tires in the process or bend anything.. It's hard to admit when you screw up.. might as well do it on the internet! LOL
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