Minor bump steer at freeway speeds

[caleb]

I’ve noticed that when I’m at freeway speeds (75-80mph) when I hit bumps I get a bit of bump steer effect. My truck does have the Fox Factory 3.0s, RPG UCA, RPG tie-rods, and 37” tires. It’s not scary or uncontrollable like you can get on Jeeps or Dodges, I’m more just curious is there anything I can/should do to tighten that up? If the answer is, that’s normal for these trucks, then I’m fine with that. Thanks

 

[skidmarcx]

Not sure how long you’ve had them on your truck, but I just installed my front 3.0s last weekend (still waiting on rears), so I’m still playing with compression settings, maybe try setting high speed dampening more firm? Also how much pressure are you running in your tires? Are your coil overs cranked up higher? Is your alignment dialed in? Factors that will make a difference.

 

[Donovan]

Are we not suppose to have some sort of steering wheel adjustment when we go over bumps?

Legit question on my part. This is my first truck and I thought it was just "Trucking" but maybe I need to get new shocks if Raptors are driving around like Cadillac's and mine is acting like a John Deere tractor.

 

[Tibi Steri]

I have a 2019 Raptor with just 10k miles... I don't think I ever felt the wheels steering without my steering wheel input, definitely not over small bumps. As it is explained at the following link https://www.onallcylinders.com/2014...,Steering must be locked down. More items...
it seems to be a suspension geometry issue. I would check all suspension linkages (maybe there is some worn bushing that changes the suspension geometry) and, if there is nothing obvious, I would have it checked professionally.

 

[Tibi Steri]

Are we not suppose to have some sort of steering wheel adjustment when we go over bumps?

Legit question on my part. This is my first truck and I thought it was just "Trucking" but maybe I need to get new shocks if Raptors are driving around like Cadillac's and mine is acting like a John Deere tractor.

My 2019 has a "trucky" feeling when I hit series of smaller potholes.... The bigger the pothole the more comfy the suspension gets... I did not have to adjust steering even after some moderate truck "jumping"...

 

[caleb]

To be clear, the bump steer I'm talking about is at freeway speeds and hitting bigger bumps like an overpass transition. Again, it's not significant, but does exist. It's not just being a truck. For reference, my 2017 Raptor did not exhibit this but it was bone stock. So that's why I was wondering if, when modified, this is normal for these trucks.

 

[smurfslayer]

If it’s ‘normal’ it’s not desirable and I would venture to say it’s less than safe if there is either higher speed street driving or high speed off road driving in the truck’s future. You said it yourself, the stock suspension ’17 didn’t do this and I can confirm this.

I think from what you’re describing the rebound damping may be too stiff, transmitting too much of the impact into the suspension and steering as a result. non compliance in the suspension can definitely compromise control.

 

[Raptor 2014]

What are your current alignment settings.
I had a shop install upper control arms, tie rods, rebuild my 3.0 shocks and custom Deaver springs a few years ago. I was very sick at the time and didn't want to do it myself. Evil Manufacturing La Habra - They did a great job. They sent it to an alignment shop and I asked for the alignment to be set at 7 degrees caster, negative 1-1/2 degrees camber and 3/32 to 1/8"toe. I got a alinement sheet to verify and when I checked it was not even close - the truck tracked straight but way off from what I asked. I spent the next full day correcting it. PIA because of health at the time and taking measurements off my Bead Lock wheels was exceedingly difficult with the equipment I had. - 1st gen

 

[Macdaddy]

I have a stock 2020 and are you talking about when you hit a “bump” “hump” or “heavy transition” at highway speeds only above 60moh I’ve found, the rear end jumps kind of to the side? It has to be shocks or something, when I’m towing my trailer at same speed it really limits how it jumps to the side a lot. Other guys in here will have better answers I’m sure, I’m just saying I have it and just live with. Not so bad I need to find a fix.

 

[Granelli]

I've got a supercab with the 3.0's. It will occasionally run with a groove on the road or pull funny. Hitting bumps on the freeway/joints that are perfectly perpendicular causes this "bump steer" as well. I think it's the nature of the beast at times. Wide track, wide/soft tires that never will wear like a car tire, and bypass shocks.