3rd gen tacoma steering wander/ bumpsteer

This is how my truck sits. About 1 inch higher in the rear.
Im sitting on fox 2.5 kit front and rear
spc uca
ironman4x4 leaf springs
285/70/17 bfg ko2’s load range c @30 psi
rrw RH-7 17x8 +0 offset wheels

Alightment specs are
Oem spec toe
Oem spec camber
4 degrees of castor.

My truck does have some tramlining. What bothers me is the jerking in the steering wheel when going over potholes/ manholes. Very floaty on the highway.

Also like to mention. This is a new set of suspension and this issue started when I had an eibach kit on.

I appreciate everyones help, Thank you.

 

Hey, I had a little bump steer too on my truck and mine also wanders a little.

I have experience with my truck and as an Lift tech.

For the bump steer it's kinda how these trucks are because with the shocks being so soft and bump stops so... lackluster... when the shocks top out which is expected on these trucks then the jarring of the near useless bumpstops the toe change over is more pronounced and noticable. My solution on my truck was the durobump, bumpstops, if you're looking for it you can feel it but it's otherwise invisible to the average driver. The other possibility is uneven tie rod lengths ( could also be a steering rack not centred) because then when the suspension is jouncing then rebounding the toe change will be different and steer your car in a direction. The other possibility I suspect but can't verify for you is the weak rear leaf hangers are flexing and steering the rear. I'm on factory hangers still so I can't say it will correct your issue but it's a though

for your tramlining/ wandering it's since normal as caster spec for these trucks is only around 1.5-3* which is a little low in my opinion but you have aftermarket uca so disregard that. Try alignment specs of near 1* POSITIVE Camber. Positive camber is the secret most alignment guys don't know about especially in regard to running negative offset wheels. The reason for this is because negative offset wheels more the scrub radius away from it's intended spot which reduces straight line stability. Negative camber will cause more wandering. I would recommend a spec of 1* positive camber for both sides and 4* caster left and 4.5* caster right ( to compensate for road crown) and go from there wider tires are more resistance to alignments so you may have to get close to a 1* caster split depending on how wide your tires are. For toe, always toe in for a road vehicle. I found 0.06" to drive the nicest but to also start cupping tires if you slack on rotations. I would not run less than 0.04" because i've found these trucks are not good at highspeed straight line driving and need all the help they can get in that department. Tire tread is also a factor. For example all seasons with a solid rib down the middle with driver straighter than a all terrain with only staggered tread blocks running down the middle

p.s my personal alignment setting on my stock truck are 0.6* POSITIVE camber on both sides 2.25* caster left and 2.75* caster right with 0.05" total toe and I have no bumpsteer and minimal tramlining on the highway(currently) running 265/70r17 winter tires (Cooper Snow Claws at 32 psi

 

It’s all in the alignment settings.
A good shop with experience dealing with lifts can fix this. The boys down at Midas…….most, not do much.

Factory alignment specs often don’t work for lifted trucks

 

How much lift in the front?

 

Maybe a cab mount loose or needs replacement. Those are notorious failures for these trucks

 

2.5 in the front

 

2" is generally considered the max...
When you bump on just one side, does it steer inward?

 

Passanger tire is definitely more noticeable but both do it. Ive had the lift at 2” lift setting. Made absolutely no difference.

 

Also I have been noticing clunking at full lock while in reverse. And if i hit a bump while turning you can hear a rattle/ clunk. Almost like a sway bar link. (Sway bar bushings and links are brand new) been chasing this for 25k miles now hahaha.

 

Right...
But you're steering and suspension geometry in relation to instant center are 'off'; coupled with too short a tie rod length...

Do you have the extended travel coilovers?

 

Yes i do have extended coilovers. I have an appointment for an alignment tomorrow. Was going to have then put the castor at 4.0 drivers 4.5 passengers. +1° of camber on both sides. See if that helps any. How do i know if my tie rods are too short? Would they bind and full droop? Sorry im just trying to understand what you are explaining a little better. Thanks again for the help

 

Note i do not have long travel. Just a standard fox 2.0 coilover with the preload adjusted a bit to compensate for the weight of the front bumper and lights

 

Maybe take a peak and try to measure to ensure your steering rack is centred before the alignment but the downward angle of the tie rods with a lift will cause more toe change over bumps because the travel arc of the tie rods will steer the wheels more. Also 1* of camber POSITIVE will help but note the peigon toe may be noticable to you, fore warning

 

Great suggestions here!

Have you checked for a bent Spindle?

Also, maxed out preload could be a thing. I personally have Dobinsons MRR's with 252 coils, but will be switching to 254 coils to allow more range and not so much preload.

 

I don’t believe my spindles are bent. Nor do i think this preload is maxed out. Also i have the sway bar removed for the day to see if it made any difference. Nothing noticeable yet. Do my tie rod angles look too extreme?

 

Do you have a spacer lift on top of your shock mounts? Post a better pic of the top of the front shocks

 

I do. I have a 1/2 spacer on both sides. I have removed this and gotten a new alignment. Resulted in no change is driving characteristics. Just got a super loud clunk when i was parked and i turned to the drivers side

 

It's not much your tie rod angles are extreme. Not ideal yes but unless you replaced it with a knuckle that would have the tie rod mount back in line with the rack thats how the angle will look. The big thing to take from looking at the angle is to picture that even though the tie rod is moving in a circular arc the ball joints keep the knuckle steady so the tie rod moving from a not level angle will steer the wheels more and if you for say hit a dip in the road and had a go pro on a car in front of yours rear bumper you would see a big tire steer

 

What is the process to fix the bump steer? And it really feels like the tires move independently from the steering wheel. Like they move side to side without steering wheel input. Tie rods are all solid though. This truck was in a front end collision before it was mine. Thats one of the main reasons i think a bearing/ gear is messed up in the rack. Also this has been progressively getting worse.

 

To me, it looks like you're maxed out on preload, and the 1/2" spacer is essentially adding that much more in thread count. Fox 2.0 are for stock trucks with some leveling involved (edit: he has 2.5s). It seems you need a more robust solution for your needs. Just my two cents, and I'm not sure if it's the contributing factor to your situation. If you haven't seen, check Tinker's videos: