Fuck turning wrenches, I wanna go wheeling; Build and BS

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View attachment 6108
Mock up for my anti-bump steer solution.

This will move the steering pickup forward and up (closer to the UCA), changing the steering tie rod length and angle to properly match the rest of the suspension.
So I'm trying to find ways to deal with destroying the top bushings on my steering rack every couple thousand miles and looking for ways to prevent/minimize the vertical deflection on the rack.....

What are the issues with just moving the steering joint above the OEM mount? I'm thinking about drilling out the OEM mount and then mounting a heim & misalignments and adding a double shear at the top of it for extra strength. I've seen folks do this to other vehicles but none on our trucks. I'm sure there are some downsides to this but can't find anything.
 

Arcticelf

Head BFH Operator at Gray Man Fab
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DelCo PA
So I'm trying to find ways to deal with destroying the top bushings on my steering rack every couple thousand miles and looking for ways to prevent/minimize the vertical deflection on the rack.....

What are the issues with just moving the steering joint above the OEM mount? I'm thinking about drilling out the OEM mount and then mounting a heim & misalignments and adding a double shear at the top of it for extra strength. I've seen folks do this to other vehicles but none on our trucks. I'm sure there are some downsides to this but can't find anything.
Bump-Steer. Moving the center point of the tie rod pivot changes the relationship between the tie rod and the control arms. Your spindle moves on a 3 dimensional arc as the suspension articulates, and if the outer tie rod pivot doesn't follow the same arc you'll get bump-steer: a tendency of the wheel to "steer" (that is move like you were providing steering input) when the steering wheel is stationary and the tire is moving through the range of suspension travel. Moving the pivot point up will cause the wheel to toe-out under compression, and toe-in under droop. This can set up a very violent oscillation in the vehicle.

Why do you think the tie rods are causing vertical deflection in the rack? Unless they are binding that shouldn't be an issue.
 
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Bump-Steer. Moving the center point of the tie rod pivot changes the relationship between the tie rod and the control arms. Your spindle moves on a 3 dimensional arc as the suspension articulates, and if the outer tie rod pivot doesn't follow the same arc you'll get bump-steer: a tendency of the wheel to "steer" (that is move like you were providing steering input) when the steering wheel is stationary and the tire is moving through the range of suspension travel. Moving the pivot point up will cause the wheel to toe-out under compression, and toe-in under droop. This can set up a very violent oscillation in the vehicle.

Why do you think the tie rods are causing vertical deflection in the rack? Unless they are binding that shouldn't be an issue.
I can see it watching the steering cycle and it's destroying the flanges on the poly bushings, as far as what I'm noticing it looks like what's going on:

Steep tie rod angle due steering connection at the bottom of the spindle joint and vehicle being lifted
+
37s causing heavy resistance
=
the rack being pushed up at the ends as the steering cycles

When you modified your joint did you keep it at the same height as OEM?
 
Last edited:

Arcticelf

Head BFH Operator at Gray Man Fab
Joined
Apr 23, 2019
Messages
833
Location
DelCo PA
I can see it watching the steering cycle and it's destroying the flanges on the poly bushings, as far as what I'm noticing it looks like what's going on:

Steep tie rod angle due steering connection at the bottom of the spindle joint and vehicle being lifted
+
37s causing heavy resistance
=
the rack being pushed up at the ends as the steering cycles

When you modified your joint did you keep it at the same height as OEM?
The first time, no. I just dropped a heim joint under the spindle and gave myself massive bump steer.

The second time, when I did the double shear mounts I corrected the bump steer, but moved it forward for more steering leverage and lost turning radius.

The right way to do it is to cut off the OEM steering pickup from the spindle and weld on a new double shear that is in the correct vertical orientation.

Unfortunately I'm not sure that would help you, since the pivot location still needs to be in basically the same place.to avoid bump steer.
 
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The first time, no. I just dropped a heim joint under the spindle and gave myself massive bump steer.

The second time, when I did the double shear mounts I corrected the bump steer, but moved it forward for more steering leverage and lost turning radius.

The right way to do it is to cut off the OEM steering pickup from the spindle and weld on a new double shear that is in the correct vertical orientation.

Unfortunately I'm not sure that would help you, since the pivot location still needs to be in basically the same place.to avoid bump steer.
Bummer, I was hoping there was a solution at the spindle end. I'll probably end up trying custom delrin bushings for the rack and see if they hold up better than the poly.
 
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Bummer, I was hoping there was a solution at the spindle end. I'll probably end up trying custom delrin bushings for the rack and see if they hold up better than the poly.
Solid mount the fucker. Only downside is increased vibes through the steering wheel.
And possibly more bending of inner tie rods.
 
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Solid mount the fucker. Only downside is increased vibes through the steering wheel.
And possibly more bending of inner tie rods.
I've thought about it, but worried that the stresses will just completely break the mount off the passenger side of the housing. However going to delrin will increase that risk as well. :noidea:
 

Arcticelf

Head BFH Operator at Gray Man Fab
Joined
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Messages
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I've thought about it, but worried that the stresses will just completely break the mount off the passenger side of the housing. However going to delrin will increase that risk as well. :noidea:

Delrin is marginally softer than Aluminum, so you'll get some benefit.

Do you have a pic of the setup you have now? I'm curious what about your set-up is driving the rack up like that.
 
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Delrin is marginally softer than Aluminum, so you'll get some benefit.

Do you have a pic of the setup you have now? I'm curious what about your set-up is driving the rack up like that.
I've seen some other folks mentioning noticing the same thing for them, but none have 37s, might be the little bit of extra tire adds enough stress to cause more vertical deflection.

Just a TC +2 race kit on 37s
IMG_20190921_090620.jpg
 
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I've seen some other folks mentioning noticing the same thing for them, but none have 37s, might be the little bit of extra tire adds enough stress to cause more vertical deflection.

Just a TC +2 race kit on 37s
View attachment 16324
Have to say that the TRE extension and the angle of the assembly at full droop will definitely cause more upward force on the rack. Exactly how many inner tie rods have you tweaked? If you are trashing the rack bushings and not the inner tie rods that is a testament to your driving finesse.
Delrin will still fail albeit not as soon as poly.
I say solid mount the rack at this point.
Keep in mind my experience is limited to poly rack bushings, stock length UCAs and LCAs and 35s. But I have managed to bend at least 3 inner TREs that I can recall
 
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