Hypertech Speedometer Calibrator (1 Viewer)

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Now the question is, does it only fix the speed in the instrument cluster or does it actually correct it for the ECM/BCM/TCM.
On the website they cleverly stated the obvious that non-stock tires will through off the Transmission shifting but they technically only state it corrects the speedometer. "Part-throttle shifting" can mean that is changes the throttle response and not necessarily correct the speed signal in the computer.

To me if that's the case its not worth it, now if it also fixes the transmission shifting then I would be interested

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I suspect not. It consists of a little module and a wiring harness that inserts the module into wiring behind the instrument cluster. I doubt the ECM collects any data through that particular wiring.
 
I finally got around to installing the Hypertech Speedometer Calibrator today. Install is pretty easy, a video from GX BOB was useful in removing the instrument cluster. Only 2 screws and everything else pops off. The unit just plugs in inline with the supplied wiring harness.

Alas, the properly configured unit did NOT do anything to change the speedometer reading for my 2018 GX, so it is going back.

I wouldn't be surprised if this unit did actually work on older GXs... but I have no way of knowing either way.
 
I finally got around to installing the Hypertech Speedometer Calibrator today. Install is pretty easy, a video from GX BOB was useful in removing the instrument cluster. Only 2 screws and everything else pops off. The unit just plugs in inline with the supplied wiring harness.

Alas, the properly configured unit did NOT do anything to change the speedometer reading for my 2018 GX, so it is going back.

I wouldn't be surprised if this unit did actually work on older GXs... but I have no way of knowing either way.
So all that work was for not?
Just curious, why do you think it'll work on older GX's? Do you mean GX470 or the '10 - '13's?
My guess unless you had a 2022 or newer and it didn't work on that, then maybe, and that's a big maybe, it'll work on older GX's.
But I don't think there's really any difference behind the dash between your 2018 and my '13.
 
Just looked up Hypertech Speedometer Calibrator and they specify ALL our GX's!
And you say it didn't work?? Hummm. Something sounds hinky.
 
I talked to Hypertech tech support and they were able to view my unit's configuration on line and said it was correct, but when installed it had no effect on my speedo reading (I tried twice). No way to know if the unit was somehow defective otherwise.
 
So all that work was for not?
Just curious, why do you think it'll work on older GX's? Do you mean GX470 or the '10 - '13's?
My guess unless you had a 2022 or newer and it didn't work on that, then maybe, and that's a big maybe, it'll work on older GX's.
But I don't think there's really any difference behind the dash between your 2018 and my '13.
Maybe not. I just know some electronic items on the GX460 changed multiple times through the years (parking sensors are one example), so maybe something changed in the speedometer function too. But it is just speculation, I could easily be wrong.

In any case I would really be interested to hear of any other experiences with this unit in a GX460, because I am left wondering if this is a systemic problem with the GX460 or a problem with the individual unit I had. Surely somebody else has tried it?
 
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Does anybody know where the GX derives its speedo data from?

I got to thinking about this during the long drive to Utah, and it occurs to me that the speedo should actually be reading high with 4.88s and 35s, rather than low... that is IF the GX used an old school speedo drive from the transmission. Instead, the speedo is reading 10% low, which means the GX is getting speedo data from something like a wheel speed sensor.
 
Does anybody know where the GX derives its speedo data from?

I got to thinking about this during the long drive to Utah, and it occurs to me that the speedo should actually be reading high with 4.88s and 35s, rather than low... that is IF the GX used an old school speedo drive from the transmission. Instead, the speedo is reading 10% low, which means the GX is getting speedo data from something like a wheel speed sensor.
Unsure where the GX gets its signal? That being said when I regeared I had to adjust my Scan Gauge a few %. The speedo still reads low. IDK why? 285/75/17 or 34"tires and 4:88 gears, it should be reading a bit fast?
 
Unsure where the GX gets its signal? That being said when I regeared I had to adjust my Scan Gauge a few %. The speedo still reads low. IDK why? 285/75/17 or 34"tires and 4:88 gears, it should be reading a bit fast?
It definitely *should* be reading fast. The fact that it isn't suggests a data source somewhere other than the drivetrain.
 
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Thanks Acrad... and I assume the skid control ECU gets its information from the wheel speed sensors, as I thought. Interesting... not sure what I can do with that information with regard to speedometer correction, but good to know.
 
Unsure where the GX gets its signal? That being said when I regeared I had to adjust my Scan Gauge a few %. The speedo still reads low. IDK why? 285/75/17 or 34"tires and 4:88 gears, it should be reading a bit fast?

Adjusting it on the Scan Gauge just affects the ScanGauge. Speed readout, mileage, etc.
 
Figured I'd try again... ANYBODY tried the Hypertech Speedometer Calibrator #730135 on a GX460? They still list it for a GX460.
 
Not a direct answer to your question... but I'm successfully running a SpeedoHealer on my 470. On the 470, the speed sensor output goes into the back of the instrument panel. Actual speed readings come from the wheel sensors. The SpeedoHealer intercepts and corrects the signal before the speedometer gets it. Since the odometer and MPG calculations are downstream, they get corrected too.

It might be worth looking at a 460 FSM and examining the wiring diagram for the instrument panel to see if it works the same way. Both vehicles do share a lot of electronics. The SpeedoHealer does require cutting and splicing two of the OEM wires but is otherwise easy to install.

Edit: Here is the 470 thread I used: My install guide for speedometer correction on a 2004 GX470 - https://forum.ih8mud.com/threads/my-install-guide-for-speedometer-correction-on-a-2004-gx470.1256034/

I'm betting @Acrad can quickly tell us of a 460 works the same way.
 
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Not a direct answer to your question... but I'm successfully running a SpeedoHealer on my 470. On the 470, the speed sensor output goes into the back of the instrument panel. Actual speed readings come from the wheel sensors. The SpeedoHealer intercepts and corrects the signal before the speedometer gets it. Since the odometer and MPG calculations are downstream, they get corrected too.

It might be worth looking at a 460 FSM and examining the wiring diagram for the instrument panel to see if it works the same way. Both vehicles do share a lot of electronics. The SpeedoHealer does require cutting and splicing two of the OEM wires but is otherwise easy to install.

Edit: Here is the 470 thread I used: My install guide for speedometer correction on a 2004 GX470 - https://forum.ih8mud.com/threads/my-install-guide-for-speedometer-correction-on-a-2004-gx470.1256034/

I'm betting @Acrad can quickly tell us of a 460 works the same way.
Do you have a link to the SpeedHealer?
The https://www.amazon.com/Hypertech-730135-Speedometer-Calibrator-2010-2018/dp/B09X3YKCSQ is a little pricey.
 
I got mine from Bayside Performance. These are made for sport bikes, but do work fine in at least the 470. Looking at the Hypertech calibrator, it appears to do the same thing as the SpeedoHealer (intercept the speed signal and modify it).

SpeedoHealer ($80 on sale): Healtech SpeedoHealer V4.0 Control Unit - Bayside - https://www.baysideperformance.com/healtech-speedohealer-v40-control-unit#/32122-control_unit-sh_v4
Universal harness ($30): Healtech SpeedoHealer V4.0 Harness Only Offroad - Bayside - https://www.baysideperformance.com/healtech-speedohealer-v40-harness-only-offroad#/40468-harness_kit-sh_u01_universal

I mounted mine in a cubby I made for the old DVD player above the glovebox, as I had the dash off anyway, and it was easy to run wires from one side of the rig to the other. Had the dash been on, I would have tucked it up under the driver's side lower dash, probably with a Velcro mount so it could easily be removed for calibration. It does require a IGN + power source and ground. A fuse tap to something like the cigarette lighter circuit would get it the IGN + and the ground could go to anything metal under the dash.

The nice thing about this unit is that, in the event of unit failure, it can be easily unplugged and speedometer function can be restored by jumping the signal-in and signal-out pins in the connector.

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