My truck is trying to kill me?

I have a 2014 TRD off-road (4WD), with a scary problem. Occasionally (4 times in the past month) it goes <clunk> and steers hard to the left. So far this has only happened in 2WD on pavement, on twisty mountain roads in tight right-hand curves.

I don't *think* there were any dashboard warning lights when this happened, but since the truck was trying to steer me into the oncoming lane in a blind curve, I was not really paying a lot of attention to the dashboard at that point. An OBD2 scan shows nothing, tried 2 different scanners.

All attempts to reproduce the problem have failed. It happens when it happens, but I can't deliberately cause it. My mechanic has been all over it and has test driven it without finding anything. I'm at the point of just replacing stuff hoping the problem goes away. I HATE that.

Any ideas? Anyone ever have a similar problem?

 

do you know if the VSC light has come on while you’re doing this?

 

I have not seen it, but I was busy trying to get back into my own lane. If it came on it didn't leave a record for the code scanner.

 

I had a lift causing fault with my VSC on my 4runner that literally did what you have described.

 

May just need a VSC reset especially if you have recently had any suspension work/alignment/tires done.
https://www.tacomaworld.com/threads...ibrate-your-vsc-computer-the-easy-way.467485/

If you have a lift/oversize tires there might not be alot you can do as the VSC system on 2nd gens doesn't play well with certain lift/tire combinations.

 

Do a search for VSC calibration.
Is your steering wheel straight, when driving down a straight road?

 

#1: Do you feel the steering wheel try to turn in the direction of the veering?
If not...I would be looking into the third member. On rare occassions, but not unheard of, there has been third member failures.

I think it was in 2021, I was driving at about 40 and had just crossed over a very smooth RR crossing and a few yards after the crossing, my 01 2WD suddendly my truck went hard left and crossed the double yellow. And it sounded like someone was under the truck, banging with a big hammer. Going under 15mph, no problem. Over that was. Now mine was a catistrophic failure. I was not too upset. It had 231,k on the clock. Found a very lightly used axle and did a complete replacement.
***I never did feel anything in the steering wheel.***
Last thing: I did tear out the third member but I could not find or see any issues.
Just my thoughts.

 

My steering wheel is straight, but they recently straightened it. After some front suspension work (replaced the lower control arms) it was not quite straight, and I drove it like that for several weeks before getting it fixed. And yeah, the steering wheel turns in the direction of the pulling.
I have a small (1-1.5) inch lift, running 265/75R-16 KO3's. The VSC calibration sounds like a really good idea, I'll pursue that.
Thank you all for the ideas and input!