'Loose' steering

[OakieEd]

Just bought this 2006 LX470 140,000 mi to replace my high mileage 2001. Horrible handling. Found loose rack. Installed new rack bushings. Exhausting to drive straight. Doesn't just wander, but needs constant correction to keep from going off the road. Wind, road groves etc slide it all over the road. All tie rods, ball joints, control arms, bearings are 'tight'. Had it Lexus dealer aligned. Mechanic has no idea what the problem is, Said it's too bad I can't turn off VGRS. Just seems like loose steering at zero position. Drives OK on a curvy road.

 

[2001LC]

Any: Mods or all stock? Any accidents?
Knowing the history of vehicle service, mods and accident is where I start.

The issue could be in control arms or stabilizer system even alignment not done to spec. Which includes cross leveling, making sure at least 3/4" rake (front lower than rear), setting AHC pressure correctly and zero point calibration (in brake, ABS). These things just aren't done, even by most Lexus shops, during alignment service. But he factory manual call for then to be checked and corrected if need be.

I'll focus on VGRS, just because you mentioned it!
One of the few things known to damage VGRS actuator: Frontal impact. Causes:

• Accident.
• Also when rack & pinion (R&P) immediate shaft removed. Like when R&P or DS exhaust manifold replaced or VGRS snap ring recall service done. Mechanic often use an air hammer to pound off intermediate shaft from R&P. This is a big NO NO in VGRS systems.

There is a warning in the snap ring recall TSB procedure, that states: Do not pound upward (in direction of steering wheel) on intermediate shaft. Doing so can damage VGRS actuator.

Additionally. The VGRS has procedure to do full calibration, that one part is so often missed. It the first thing we must do. Which is "clear all "flags". Is mostly not, most never even notice the flags or know to look.

Also guys that have removed AHC, sometimes cause a fault in ABS, that feels like steering system issue. It actually ABS kicking on, and feel like steering issue

 

[OakieEd]

Any: Mods or all stock? Any accidents?
Knowing the history of vehicle service, mods and accident is where I start.

The issue could be in control arms or stabilizer system even alignment not done to spec. Which includes cross leveling, making sure at least 3/4" rake (front lower than rear), setting AHC pressure correctly and zero point calibration (in brake, ABS). These things just aren't done, even by most Lexus shops, during alignment service. But he factory manual call for then to be checked and corrected if need be.

I'll focus on VGRS, just because you mentioned it!
One of the few things known to damage VGRS actuator: Frontal impact. Causes:

• Accident.
• Also when rack & pinion (R&P) immediate shaft removed. Like when R&P or DS exhaust manifold replaced or VGRS snap ring recall service done. Mechanic often use an air hammer to pound off intermediate shaft from R&P. This is a big NO NO in VGRS systems.

There is a warning in the snap ring recall TSB procedure, that states: Do not pound upward (in direction of steering wheel) on intermediate shaft. Doing so can damage VGRS actuator.

Additionally. The VGRS has procedure to do full calibration, that one part is so often missed. It the first thing we must do. Which is "clear all "flags". Is mostly not, most never even notice the flags or know to look.

Also guys that have removed AHC, sometimes cause a fault in ABS, that feels like steering system issue. It actually ABS kicking on, and feel like steering issue

Great info. Thanks! No accidents. No mods. All stock except slightly larger BFG KO2s(brand new). AHC works great. Always serviced at Lexus. But few big items ever done. I just bought it at a Lexus dealership at 140K and they did the timing belt for the sale (as well as all the brakes and rotors)...so it wasn't done at proper service interval. They 4 wheel aligned it, but sent me down the road with a totally loose steering rack. Once I fixed that I took it to my Lexus dealership and they found bad toe..so they aligned. Where should I start?

 

[2001LC]

• Make sure rack and intermediate shaft bolts all the way to steering wheel, torqued to spec and all U-joint in perfect condition.
• Make sure all inner and out TRE locked in/tight and good working order.
• It is not likely with OEM rack & pinion, that the pinion gear not be properly preloaded. But can't say the same for remain or aftermarket junk. I've one that steering feels just a tad loose. I get just a tad bit of wiggle/loose in steering. I've track it to (I believe) preload of pinion gear. I'll not know, until I correct preload.
• Make sure steering wheel top nut, torqued down.
• Make sure wheel bearings preload set (tight bearings), to spec.

In tech stream:

1. The zero point calibrate (brake)
2. In VGRS clear all flags
3. Calibrate VGRS. This includes as if VGRS CPU replaced. It's a -- start engine- turn wheel- engine off- turn wheel- 15 times procedure. Lexus Dealerships, have the snap ring recall TSB, which has this procedure. It's also in the FSM.
4. Zero steering wheel.
5. Driving calibration.

One (non VRGS) I worked on. Owner said he had many Dealerships shops and alignments shops, work to get pull out. None could get, pull out.
I replaced LCA and #2 bushings. I had to use extra spacers on #2 bushing, for proper fitment on LCA. When done, owner reported. "That for the first time, it didn't pull". This was even before and after alignment. I've since found another, in which I had to use extra spacers in #2 bushing to get proper fitment of LCA. Both are "believed", to have had front end damage. Neither on carfax.

You may also want to have frame measured. Most large cities, have one or more places to get this done.

It unusual to replace R&P, by 140K. The R&P loose mounting bolts, indicates poor workmanship. Likely more worked on your 06LX and more things screwed up. I spend most days, correcting what others have done.

If all else fails, bring or ship it to me.

 

[OakieEd]

The zeroing and calibration of the VGRS did wonders! Thanks!