2010-13 vs. 2014-Up GX460 Turning Radius (7 Viewers)

[Rollover]

Any clue why the 2014+ GX460's have an increased turning radius? The T4R stayed the same.

From Toyota's product information.

2013 GX460 Turning Circle 38.1ft
2014 GX460 Turning Circle 41.4ft
It's almost exactly a meter difference (1.00584)

Is it a clearance issue with the newer front end? If you ditch the front bumper can you get the turning radius back to the 2013 specs?

Thanks in advance,

 

[r2m]

To your question, I have no idea why the 14+ requires more real estate to make the same turn.
Regarding turning radius measurement, I believed it is done from the front outside wheel, the radius that it makes. Bumpers don't factor into what a turning radius would be. Consider a "U" turn. Generally all you're concerned with is that you don't go up the curb or scrub your front tires in completing your turn. You're not concerned about the bumper hitting anything, just the curb. Even the bumpers/grill on the 14+ GX's will do that on most all curbs.

 

[Ol Yeller]

I’m very curious to hear this one answered, I never noticed the difference when I was researching our purchase.

 

[Rollover]

Thanks R2M... and 22Eynun35VO. It just seems so strange. The T2R and GX sharre the same frame and suspension, but the GX takes almost exactly a meter more to make a U turn.

Note: The Prado has a turning RADIUS of 5.8M if you double that and convert to feet it works out to 38.0578 or rounded 38.1 feet just like the T4R.

Time to break out the chalk at your local parking lot and actually measure.

 

[Acrad]

Someone does need to measure. Every Lexus Product Description sheet and brochure since 2014 has stated the 41.4 foot turning circle on the 460.

 

[Acrad]

Could it be that the 10-13 and '14+ have different alignment settings? Can't this affect turning radius? Alignment knowledge weak here.

[10-13]

'14+

 

[Acrad]

More '14+

 

[r2m]

Regarding the Prado, although it does have the same frame and body, everything from the firewall forward is different: engines, weight, emissions, layout, etc. which could mean different front suspension components too.

 

[Rollover]

22Eyunu35VO, I'm no alignment expert either... Thanks for digging this up, maybe some experts can chime in on alignment and turning radius.

R2M , Good point on the Prado, but the T4R is also all different from the firewall forward and it shares the same turning radius specs as the Prado.

I'm on the fence with a 2013 or 2014+. The main advantage of the 2014+ is more availability and newer without spending much more. The downside turning radius and front bumper options.

 

[BMRisko]

The downside turning radius and front bumper options.

There really aren't that many more front bumper options for the 10-13. Personally, I think the ARB/Ironman style looks awesome, especially on the 14+. Yea, you have to cut the oem bumper cover, but not really that big of a deal.

 

[tortoiseracing]

Based on what I found, the following parameters are identical for the 2010 and 2014 GX 460:
* Steering ratio (18.4:1)
* Steering wheel lock to lock turns (3 turns, 1080 degrees total, or 540 degrees in each direction)
* Maximum steering wheel angle (540 degrees, based on above)
* Track width (62.4 inches, front and rear)
* Wheel base (109.8 inches)

Originally, I thought maybe the steering linkages were updated on the 2014, but if the steering ratio and maximum steering wheel angle are the same, then I think the linkages must also be the same.

Based on the information 22Eyunu35VO provided:
The recommended 2010 alignment has more positive camber (0.15 deg vs. 0.03 deg). I think more negative camber on the outside wheel helps the vehicle turn. So, more positive camber on the outside wheel should hinder the car from turning?
The recommended 2010 alignment has less toe in (0.07 deg vs. 0.24 deg). To me, this is counter-intuitive to 2014 having a larger turning radius. With more toe in, the 2014's outside front wheel will steer just a little more.
The recommended 2010 alignment has less caster (3.17 deg vs. 3.53 deg). This means the 2010 settings will induce less negative camber on the outside wheel when turning. Again, I think more negative camber on the outside wheel helps the vehicle turn.

All this to say, my interpretation of what 22Eyunu35VO posted means the 2010 should have a larger turning radius, and not a smaller one. So, can somebody tell me where I went wrong?

 

[r2m]

There really aren't that many more front bumper options for the 10-13. Personally, I think the ARB/Ironman style looks awesome, especially on the 14+. Yea, you have to cut the oem bumper cover, but not really that big of a deal.

Don't forget Metal Tech bumpers!!
Also, I wonder if it isn't something as simple as where they put the stops for lock to lock? Maybe the wheel and tires changed that they needed a little more turning radius so the tires don't rub on the inside fenders/frame when hard locked in either direction, hence reducing the turning in of the tires which in turn opened the turning radius.
Hummm.

 

[tortoiseracing]

Also, I wonder if it isn't something as simple as where they put the stops for lock to lock? Maybe the wheel and tires changed that they needed a little more turning radius so the tires don't rub on the inside fenders/frame when hard locked in either direction, hence reducing the turning in of the tires which in turn opened the turning radius.
Hummm.

If Lexus did that, then the steering wheel wouldn't be 3 turns lock to lock anymore. If they changed the stops for lock to lock, it would be less turns.

 

[Acrad]

Some more '14+ data.

 

[Acrad]

More '10-13 data

 

[tortoiseracing]

Seems like the data for the 2014+ is a bit off for max wheel turn angles:

I think the 2014+ data should read like this:

Parameter	Minimum	Preferred	Maximum
Left Max Turn, Inward (deg)	34	35.5	37
Right Max Turn, Inward (deg)	34	35.5	37
Left Max Turn, Outward (deg)	32.43	32.43	32.43
Right Max Turn, Outward (deg)	32.43	32.43	32.43

Here is the information that 22Eyunu35VO provided, consolidated for ease of comparison (Thanks for providing all this information!).

Parameter	2010​	2014​
Front caster	3.17​	3.43​
Front camber	0.15​	0.02​
Toe	0.07​	0.24​
Steering Axis Inclination	12.05​	12.15​
Maximum Inside Wheel Angle	34.10 to 37.10​	34 to 37​
Maximum Outside Wheel Angle	32.62​	32.43​

If this is the case, then the numbers are very similar to the 2010-2013 numbers, meaning that the mystery lives on.

 

[r2m]

If Lexus did that, then the steering wheel wouldn't be 3 turns lock to lock anymore. If they changed the stops for lock to lock, it would be less turns.

Point taken...

 

[Rollover]

Tortoiseraracing, 22Eyunu35VO and R2M

Lot of interesting points made on the differences in alignments and steering components. Thanks for compiling all this.

RCV Performance Products makes aftermarket axles for a lot of Toyota products. One of their front axles (CVJIFS-TOY2) fits T4R's 2003+ and FJ's and GX's up to 2013. Why is the GX the only one that is cut off at 2013? I'm waiting for a response from RCV.

Pure speculation here. CV joints become weaker the more angle is applied. Since the GX is heaver, has full time 4 wheel drive and more power maybe Toyota limited the turning radius to keep folks from blowing up their axles.

 

[Rollover]

Just heard back from RCV, they say that the spline counts on the CV's are different on the 2014+.

The OEM axles have the same part number 2013 to 2014+, so I thought that was a little strange.

The mystery continues....

 

[r2m]

Sounds contrary...
2014 and newer has one spline type + 2013 & 2014+ have same part number = a wrong sum...
The math doesn't work!
Unless I read your last post wrong Rollover.