LC200 - pulling to the right / torque steer (1 Viewer)

[bartwarot]

Hello everyone,

before I get to the point I will admit that I have read all threads about this issue here and elsewhere, numerous times over last 8 months or so. I have spent tremendous amount of time and money to find a remedy... and I still I cease to give up though. Maybe some of could help or give me a hint. Thanks in advance.

ISSUE: when accelerating car pulls to the right, when deaccelerating car veers back to the left. Drives straightish under no acceleration with tendency to steer right a bit.

I have a lifted 2015 LC200 [second lift] with BP 51, adjustable Panhard rod and now SPC adjustable UCA, before it was OME UCA. Car after adding 2” lift was driving straight. Issue started with a 33” tires one day, started to pull right. I rotated tires left/right and it started to pull left. I decided to upgrade my rims and tires and went from 18” to 17” 285/75, so basically about 34” wheel. I went through several mods at the same time that now I cannot even remember, but nothing with suspension.


So in summary current state of the car:

LC200 2015, milage is 380k km

• BP51 2” lift, all shocks are on the same level left to right / front back at a slight angle.
• SPC UCA
• Dobinsons diff drop kit
• 285/75R17 wheels
• Adjustable lower control arm back
• Adjustable Panhard Rod
• Car is fully locked with ARB lockers

What I did to fix my issue:

• Changed lower control arm in the back to add adjustability in my geometry
• Changed all bushings front and rear
• Changed tie rods ends, regenerated steering rack = inner steering rods and exchanged inner bushings
• Changed right CV [boot was leaking and was in bad shape]
• There seems nothing to be loose or worn off
• Went throught 20+ geometry and different settings in 4 different shops

What else can I do?:

• Look into front differential gears?
• VGRS – can this piece of electronics be responsible – can it be swithed off for diagnostics?
• Gear box? – I don’t think so

Please let me know what you think, any idea or solution would be nice.

PS: English is my second language, so I might not know all the part names of top of my head

 

[TeCKis300]

Sounds like the classic rear toe steer due to lifted panhard geometry. A panhard correction kit/bracket is what you're looking for. There are finally solutions on the market. A weld on and bolt on.

Panhard drop bracket option?

Does anyone know if any company makes a panhard drop bracket to bring the rod back into a neutral position for the 200 series?

forum.ih8mud.com

 

[bartwarot]

Sounds like the classic rear toe steer due to lifted panhard geometry. A panhard correction kit/bracket is what you're looking for. There are finally solutions on the market. A weld on and bolt on.

Panhard drop bracket option?

Does anyone know if any company makes a panhard drop bracket to bring the rod back into a neutral position for the 200 series?

forum.ih8mud.com

Wouldn't the adjustable panhard rod fix the issue? Already have one

 

[TeCKis300]

Wouldn't the adjustable panhard rod fix the issue? Already have one

Not really. The problem really is the angle of the pan hard rather than the length. Length only fixes the static alignment. The steeper angle creates toe steer as a suspension cycles which is the problem here. With the panhard bracket the adjustable rod is arguably even necessary.

 

[bloc]

Also, how much offset on the wheels?

 

[bartwarot]

Also, how much offset on the wheels?

25mm =

ICON REBOUND 17X8.5 5X150 25MM OFFSET 5.75IN BS 110.1MM BORE BRONZE WHEEL​

 

[bartwarot]

Not really. The problem really is the angle of the pan hard rather than the length. Length only fixes the static alignment. The steeper angle creates toe steer as a suspension cycles which is the problem here. With the panhard bracket the adjustable rod is arguably even necessary.

Thanks for suggestion, I ordered one. Once it arrives we will see if this helps with my issue. Are you running apanhard bracket?

However, my car made 15k on BP51 and 2" lift before this started to occur. This puzzles me.

 

[hoser]

Went throught 20+ geometry and different settings in 4 different shops

You said 2" lift but what is the measurement between the center of the wheel hub and the front fender lip?
What are your alignment specifications, particularly "Caster?" Also, if you swapped the tires/wheels left to right and the "Pull" changed accordingly, then that is certainly a factor.

 

[TeCKis300]

Thanks for suggestion, I ordered one. Once it arrives we will see if this helps with my issue. Are you running apanhard bracket?

However, my car made 15k on BP51 and 2" lift before this started to occur. This puzzles me.

I have a panhard bracket on my worktable.

It's possible the suspension was firmer or you had a lighter load early on, that gave tighter control of suspension motions. That is the rear suspension didn't deflect and cycle as much. With less cycling, you would have less resulting toe steer.

Either the suspension is broken in now or somethings changed. The symptoms are pretty normal and typical of a lifted rig.

 

[bartwarot]

I have a panhard bracket on my worktable.

It's possible the suspension was firmer or you had a lighter load early on, that gave tighter control of suspension motions. That is the rear suspension didn't deflect and cycle as much. With less cycling, you would have less resulting toe steer.

Either the suspension is broken in now or somethings changed. The symptoms are pretty normal and typical of a lifted rig.

Thanks, appreciate your reply. I ordered relocation bracket and once installed I will report back.

 

[linuxgod]

You said vehicle pulled right, you swapped tires left/right and now it pulls left? If that's the case, I'd look into new tires.

If you have a copy of your alignment specs that can help confirm your alignment is set up well (not just "good enough")... alignment alone won't solve your issue but it will amplify it.

That said... the pull you have is "normal" for a lifted truck, and it's worse when you're hard on the throttle. There are some things you can do to make it better, though you'll likely never eliminate it unless you go back to stock suspension.

• First, check your vehicle height in each corner. Are you level left-to-right in the front and in the rear? Any lean, especially up front, will make the vehicle torque steer like this in my experience. You might need to adjust the coilover preload a few mm in the front, or add a trim packer to a rear coil to get yourself level
• The bolt-on panhard correction bracket will help, as it will help you get the panhard rod back to level. That, combined with re-adjusting your rear panhard rod to get the rear end lined up with the front will help.
• Another thing is optimizing your wheel offset for the scrub radius, which likely means trading in your +25 wheels for something around +42 which is closer to optimal for a 34" tire. (I've run +25 offset on 34s and 35s and I'm fine with the slight torque steer but for +25 offset you really need to be on 37s I think to get the optimal scrub setup)

 

[AnyMal]

Idk it could be a variety of things. One thing i am sure of is the profile pic being S tier. Lol

As far as your post, when you say decelerating, do you mean brake application?

 

[bartwarot]

You said vehicle pulled right, you swapped tires left/right and now it pulls left? If that's the case, I'd look into new tires.

If you have a copy of your alignment specs that can help confirm your alignment is set up well (not just "good enough")... alignment alone won't solve your issue but it will amplify it.

That said... the pull you have is "normal" for a lifted truck, and it's worse when you're hard on the throttle. There are some things you can do to make it better, though you'll likely never eliminate it unless you go back to stock suspension.

• First, check your vehicle height in each corner. Are you level left-to-right in the front and in the rear? Any lean, especially up front, will make the vehicle torque steer like this in my experience. You might need to adjust the coilover preload a few mm in the front, or add a trim packer to a rear coil to get yourself level
• The bolt-on panhard correction bracket will help, as it will help you get the panhard rod back to level. That, combined with re-adjusting your rear panhard rod to get the rear end lined up with the front will help.
• Another thing is optimizing your wheel offset for the scrub radius, which likely means trading in your +25 wheels for something around +42 which is closer to optimal for a 34" tire. (I've run +25 offset on 34s and 35s and I'm fine with the slight torque steer but for +25 offset you really need to be on 37s I think to get the optimal scrub setup)

Thanks for your input. Stock suspension is not an option. There are several truck that my firnds have with simillar setup [LC200 + BP51 2" 33" inch] and they do not experience it or not notice it.

• I will recheck corner to corner height of my car. Is that true that LCs need to be slanted foward to get optimal aligment?
• I will install DR KDSS bracket, make back wheels straight left to right and align front again.
• scrub radius - I need to get more information about that. In europe nobody goes above 35" tyre, 34" for LC200 is considered bold already. Most guys end up on 33" max. 37" oh my god. I do not believe this is a car for such mod anyways. I will for sure stick with +25 as these rims were imported from US and cost me a liver, and looks good

Again, thanks.

 

[bartwarot]

Idk it could be a variety of things. One thing i am sure of is the profile pic being S tier. Lol

As far as your post, when you say decelerating, do you mean brake application?

Nope, just getting foot of the gas pedal. No brakes

 

[AnyMal]

Nope, just getting foot of the gas pedal. No brakes

If I HAD to blind guess, you have two or more issues. One is probably cross caster, rear axle not squared, plus drag on your damaged cv, and probably a caliper drag.

Need those alignment specs for sure.

 

[linuxgod]

Thanks for your input. Stock suspension is not an option. There are several truck that my firnds have with simillar setup [LC200 + BP51 2" 33" inch] and they do not experience it or not notice it.

• I will recheck corner to corner height of my car. Is that true that LCs need to be slanted foward to get optimal aligment?
• I will install DR KDSS bracket, make back wheels straight left to right and align front again.
• scrub radius - I need to get more information about that. In europe nobody goes above 35" tyre, 34" for LC200 is considered bold already. Most guys end up on 33" max. 37" oh my god. I do not believe this is a car for such mod anyways. I will for sure stick with +25 as these rims were imported from US and cost me a liver, and looks good

Again, thanks.

Front-to-rear “rake” won’t have an impact if the rear thrust angle is right. An alignment printout will help.

I’m guessing you’ll find your leaning to the right very slightly. Just a hunch, I could be wrong, but when I had a lean torque steer was much more pronounced.

 

[AnyMal]

Front-to-rear “rake” won’t have an impact if the rear thrust angle is right. An alignment printout will help.

I’m guessing you’ll find your leaning to the right very slightly. Just a hunch, I could be wrong, but when I had a lean torque steer was much more pronounced.

Absolutely yes ^ and will be one cause of cross caster.