Hypertech Speedometer Calibrator issues

Worked great, got mine set up after a few tries off a GPS. No issues for over a year.

 

I downgraded tire size and dumped the calibrator. Couldn’t connect and reprogram with my Mac computer and wasn’t going to send it in and pay them to recalibrate. It’s pretty close now using phone GPS with my 265/75/16s. Done messing with the calibrator. Sunk cost, but I don’t care at this point.

 

It took 7 attempts to download and install software.

I am hoping that I can leave the USB cord on this thing because my tires measure 34.5” tall from ground to top even though the specs state the tires are 33.94 inches tall (295/60R20)
I don’t want to have to pull my dash apart to adjust this thing if I can just hook a laptop up to it when the truck is turned off.

 

I left the cord on mine behind the dash and it easy to get to.

 

That’s what I am wondering, can we plug these into a laptop if they are still plugged into the Speedometer and the computer?
I’d be concerned about putting any voltage minimal as it is while it’s plugged into the truck.
have you had to change your calibration at all while it’s in your dash as it is?

 

Ronk44 you can't use a Mac computer r the software. You need to use a PC to get it done. I've had mine on my truck for 4years now and it fixed everything

 

yes I leave the usb in. Tucked in the plastic below the fuse box there under the obd.

just bring a windows laptop to it, plug it in and go.


Another tip is don’t use the metric measurement of the tire in the calibrator. Make sure your at the PSI you want for regular driving and measure the tire with a tape measure and use that as your “new tire” measurement.

there should be a second part below where you can fine tune it with the GPS speed. That usually gets it pretty accurate.

 

Thanks for the information, I ended up routing the wire down behind the centre console.
From the ground to the top of the tire is 34-3/4”
The metric tire size suggests that the tire size is 33.94” (295/60R20)

I used 33.94” and the reading is right where it should be.

I appreciate you taking the time to post up your information.

 

I also had issues downloading the software. I don't remember where but I did find another source for it and that worked fine.

I left my USB cable attached too. I make adjustments with the truck off though.

 

These things are pretty interesting. Do they affect the odometer reading at all?

 

All it does is intercept the speed signal and modifies it with a correction factor and then hands that to the combination meter. Yes, it affects both at the same time.

 

interesting…. My stock Tacoma shows a few mph high. I guess that means I am racking up odometer mileage faster than actual mileage. Over the life of the truck, that’ll add up to thousands of miles.

 

I think it was BLtheP that told me in another thread that on a stock truck the odometer is correct (I think it has to be) but the speedometer is a little off and shows you are going faster than you are. So you can decide whether to correct your speedometer and have the odometer off a little, or the other way around.

I chose to keep the odometer accurate.

 

No, they’ve got the odometer correct from factory and the speedo a bit high.

 

Correct.

 

Correct. DOT regs are that the speedometer can't read low and the odometer has to be within something like 100' accuracy.

edit: You'll find almost every vehicle to be about 3mph high at 60 from the factory.

 

Yep. Fords for me have been only about 1mph high, all others around 3mph at 60 like you said. Roughly 5%. Odometer perfect.