Oversteer?

I don't even know if oversteer is the right term. I run a 2018 SR5 Long Bed. All stock but with a little bigger tires. At highway speeds, when I'm in a long bend in the highway and hit a bump (Illinois has a few), the truck feels like it slides to the outside of the corner and the steering wheel moves just a hair in the direction of the curve.

Does that even make sense? Basically it feels like the truck is coming off the ground just a bit. It's a little freaky.

 

That's not what I understand oversteer to be.

https://youtu.be/CsVg2DE0ef8

 

Mine did this too, dclb with some all terrains on. It wasn’t that bad, since there was so much rubber sidewall for the size of the rim, I figured that’s where the play was.

 

Check tire pressures (could be over filled) and shocks for wear.

 

Sounds like bumpsteer exacerbated by suspension compression.
Aftermarket wheels with high positive scrub don't help.

It's fine on straight road with bumps?

 

Straight seems to be no problem. And I'm not sure I understood any of the other words in your post!

 

So I just watched a YouTube video on scrub radius. Kinda makes sense. Sounds like it's not an immediate problem but could add to wear and tear on the suspension over time.

 

Bumpsteer is the steering changing when the suspension cycles. Since one side is in compression, that force has no where to go except through the steering.

I see you looked up scrub...
What are the specs on your wheels?

 

I would say shocks and empty bed .

 

The problem is that the suspension did absorb the bump correctly. Odds are you where light in the back, no weight, so instead of the tires, Springs, shocks absorbing the bump, you bounce over it which upset the direction of the vehicle. If your truck had been load with 600-1000 lbs, I think this would of been different.

When I was driving in HSDE with my S2000, my rear shocks where set at full soft, the set up was done by a guy who worked on race suspension. The car handle great and I never felt the back end get lose.

We have all seen the video(s) of guys running through the desert and their suspension is just absorbing everything or driving on wash board roads and the back end is just bouncing all over the place, same principal here Our trucks are designed for a happy medium, so you can either carry some weight or get a better suspension set up.

 

My stock OR had quite a bit of bump steer on faster Corners. I've since switched to fox suspension and it seems a lot better.

 

This is all making sense now.