Handling difference with mud tire and 18”

df2x4

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Return to center should purely be a function of your (in question) alignment and freedom of movement of ball joints and tie rods.

I guess I should clarify a little bit. Over-boosted steering due to a failed or unplugged column sensor won't completely prevent the wheel from returning to center, but it can slow the process to a point where it feels "off" especially at certain speeds. For example making a slow 90 degree turn at 10-15MPH you may have to help it back to center a little.
 

Nad_Yvalhosert

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The caster angle is responsible for return to center. The higher positive caster, the better highway manners, and better returablilty.
Less caster, more wander, easy steering.
But definitely check for binding ball joints and tie rods.
 

Pinger

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boy&hisdogs

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Do the new wheels and tires stick out much farther than stock? That would make the steering feel a little sluggish.

But fix the things that are for-sure broken first, like the steering components and alignment.
 

Pinger

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Not just castor but trail, KPI and offset also affect self centering. As overall wheel/tyre diameter impacts on most of those factors, it does too. Front anti roll (sway) bar can also.
 

east302

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Do the new wheels and tires stick out much farther than stock? That would make the steering feel a little sluggish.

But fix the things that are for-sure broken first, like the steering components and alignment.

Yes, I should’ve mentioned that. I don’t know what width the rims are (they aren’t GM rims) but the tires stick out probably 1-1.5” more than stock. I don’t like them at all.

Nothing is obviously binding when watching from underneath and everything was torqued to spec.
 

Supercharged111

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Not just castor but trail, KPI and offset also affect self centering. As overall wheel/tyre diameter impacts on most of those factors, it does too. Front anti roll (sway) bar can also.

What's trail? KPI is pretty well fixed. I suspect it greatly leads caster in these rigs.
 

Pinger

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What's trail? KPI is pretty well fixed. I suspect it greatly leads caster in these rigs.

To visualise trail - look at the (virtual) king pin and see the castor slope. Now move the entire 'pin' forwards. That's trail - like a supermarket trolley wheel has.

KPI is fixed - true. But I think the longer 'footprint' of a larger diameter tyre magnifies its effect.

There's a mix of forces acting to self centre steering and their effects vary depending on what the truck is doing. Some are dependant on the grip at the road surface, others the weight on the wheels (eg, less with aerodynamic lift at speed).
 

Supercharged111

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To visualise trail - look at the (virtual) king pin and see the castor slope. Now move the entire 'pin' forwards. That's trail - like a supermarket trolley wheel has.

KPI is fixed - true. But I think the longer 'footprint' of a larger diameter tyre magnifies its effect.

There's a mix of forces acting to self centre steering and their effects vary depending on what the truck is doing. Some are dependant on the grip at the road surface, others the weight on the wheels (eg, less with aerodynamic lift at speed).

The way you describe trail sounds exactly like caster?
 

Pinger

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The way you describe trail sounds exactly like caster?

At the ground it pretty much is. But by using trail the same effect can (theoretically) be had with a vertical king pin axis - if that is desirable!
I think it's use is in combination with caster to lessen king pin angle (in side elevation view) as caster creates effects due to weight. If it is used at all these days, it is in very small amounts.
 
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