Hypertech Speedometer Calibration?

[jaychris]

Has anyone *successfully* calibrated their speedometer after wheels/tires changes using this programmer? Meaning, the speedometer and odometer are correctly reading now?

I've used it twice with different tire sizes and both times it claims a successful update. The speedometer still reads 2mph fast. And the odometer is running fast as well.

Called Hypertech and they suggested that there's really nothing that can be done, except to maybe try another tire size (maybe reduce a bit more). And that the factory settings are sometimes (permanently) off? Didn't understand that honestly.

Mainly, I'm looking to see if anyone has actually been successful in re-calibrating after changing tires and/or wheels, ideally with the Hypertech (but, anything really). Dealership said it was not a programmable component for them, so they couldn't help.

 

[RAMayor]

I did it successfully with Rough Country recalibrating tool. i just measured the height of the tires with the weight of the truck on them and used that measurement, as opposed to the specs provided from the tire maker.
I got Milestar Patagonia M/T tire, 35x12.50r22
spec height = 34.8inches
the actual height of tires measured w weight of the truck on them = 34 inches
Put that into the calibrator and the speedo read the same as waze and other GPS speed trackers

 

[jaychris]

I did it successfully with Rough Country recalibrating tool. i just measured the height of the tires with the weight of the truck on them and used that measurement, as opposed to the specs provided from the tire maker.
I got Milestar Patagonia M/T tire, 35x12.50r22
spec height = 34.8inches
the actual height of tires measured w weight of the truck on them = 34 inches
Put that into the calibrator and the speedo read the same as waze and other GPS speed trackers

Thanks! I might have to suck it up and buy the RC to try instead. The Hypertech clearly doesn't work, IMO.

 

[Twoamen]

My hypertech works fine. I installed 275 60-R20 tires. Michelin website stated 33 inch diameter. It was off by 2 mph faster. I changed to 32.75 still 2 mph off. Set to 32.50 and it's registered dead on by three different GPS speed apps. So try different settings. Recheck see attached app screen shot. It work best.

 

[Twoamen]

Biggest pain in the *** with hypertech is evertime you need to take to dealer you have to reset to factory settings. If you don't it bricks hypertech device. That to me isn't worth the purchase if I had to buy it again.

 

[Bluestreak2019]

Pretty sure the rough country one is the same as hypertech. The program it uses is hypertech. I bought the rough country for mine and put in the tire size and then would drive it to compare it with GPS speed. If it the truck was still reading faster I would back the tire size down some and then drive it again until the GPS and truck had matching speeds

 

[jaychris]

I guess I'll just keep adjusting it down until it matches or I get tired of programming. Right now, I'm at 32.5, which is a little more than 1.5" under the measured height. It's a little closer, maybe 1mph off now, instead of 2.

 

[deanfx]

I used the rough country and run 35" tires. I ended up using 33" to make it read right.

 

[GreatWhite]

I used rough countrys calibrator. Put in the exact measurement as the tires sit while on the truck and it's dead on.

 

[jaychris]

I've been working the number down. I'm at 32.25 right now which is pretty close to dead on, as far as I can tell. I would not have expected the setting to be that far off.

 

[Twoamen]

I believe To much air will add to height and to little will subtract. Weight also change diameter.

 

[chad202]

I’m pretty sure I ended up using a size 1” less than advertised tire spec in order for speedo to be right.

 

[nicodywill]

I went with the Rough Country unit after I called my dealer asking how much they wanted to update size after my level and tire swap and they told me they couldn't do it.
The dealer know about the Rough Country unit and specifically stated that if i used their exact unit it would not have any effect on my warranty so I went with them.
I measured my tire height and put that number instead of what the published dims of the tire size are and i was dead on.
I've been into the dealer for multiple services and not had any issues at all and have changed my tire setting again after my latest wheel/tire upgrade and the unit still functions flawlessly.

 

[Prioritypest]

I just did mine Saturday with the rough country and used 34.75" (35" ridge grapplers) and its reading 5mph high when going 75.

 

[chad202]

I just did mine Saturday with the rough country and used 34.75" (35" ridge grapplers) and its reading 5mph high when going 75.

My tires are 32.7", I had to use 31.75" in order for mine to read right.

 

[Whtewolf1]

does this affect transmission shifts.

 

[UKRams]

We have a 2020 Ram 1500 Limited running 35" tyres. Used the Rough Country calibrator which updates the tyre size in the BCM. We then had to also update the radio/sat nav as that didn't pickup the new tyre size straight away and the navigation goes haywire. It seems that it still uses the wheel speed pulses to calculate speed and distance travelled. After forcing the Radio to update, all is good EXCEPT the PTS (parking sensors etc.) Will not work as the PTS module reports "Vehicle Line Mismatch" and switches itself off as it doesn't like the new tyre size.

If you set the tyre size back to factory it works again, as soon as you set 34.5 (which seems the accurate rolling diameter for a 35") it refuses to operate. So we have a choice of speed under-reading by 6% and the sat-nav going haywire but having park sensors that work, or having the correct speed and no front or rear park sensors.

Dealers cannot change tyre size with wiTECH on 2020 model year vehicles, - FCA have removed the option. Even before this, dealers could only select tyres that were originally available from the factory. We have been told it is to do with the vehicles being certified by EPA with the specific tyres fitted by the factory and no EPA certification existing for any other size.

But people are going to change their tyres anyway irrespective of emissions certification.

Not being possible to correctly adjust the BCM / TCM and PTS to reflect this change is dangerous. The vehicle will either be travelling at greater speeds than indicated, or its built in safety features (Parksense) will not function properly. This is hardly ideal. It would be far safer to allow the vehicle systems to be updated to show the correct tyre size.

Has anyone had similar issues with tire size and PTS and managed to find a work around? Any help appreciated!

 

[bryan28]

Did you measure the tire by using chalk marks on the tire and pavement? I did with my Hypertech and the speedo was spot on at all speeds. Just because a tire is labeled as 35", for example, doesn't mean it is actually 35" diameter.

And I'm not sure what "everytime you take it in for service you have to reset to factory settings or it bricks the Hypertech device" even means. On the 17 Ram I used it on I never reset anything and it never changed anything.

 

[UKRams]

Did you measure the tire by using chalk marks on the tire and pavement? I did with my Hypertech and the speedo was spot on at all speeds. Just because a tire is labeled as 35", for example, doesn't mean it is actually 35" diameter.

And I'm not sure what "everytime you take it in for service you have to reset to factory settings or it bricks the Hypertech device" even means. On the 17 Ram I used it on I never reset anything and it never changed anything.

It's only if the dealer does a software update you will lose your calibration.

With regard to the PTS module we still have the issue. (2020 RAM Limited with Advanced Safety Group). We have tried both the Hypertech/Rough Country and Tazer DT and they both cause the PTS/PAM to throw the B222A-00 code "Vehicle Line Mismatch" which disables the park sensors. No amount of sleep cycles or reboots gets rid of this. All other modules are happy, speedo is spot on, Navigation is happy with distance measured vs GPS, BCM is correct, but although the PTS has the new corrected circumference in it, it refuses to operate and the code stays permanently active.

 

[Dave_Drums]

I did it successfully with Rough Country recalibrating tool. i just measured the height of the tires with the weight of the truck on them and used that measurement, as opposed to the specs provided from the tire maker.
I got Milestar Patagonia M/T tire, 35x12.50r22
spec height = 34.8inches
the actual height of tires measured w weight of the truck on them = 34 inches
Put that into the calibrator and the speedo read the same as waze and other GPS speed trackers

I'm having the Milestar Patagonia MT installed on my truck now with the 22" stock wheels from the Black Appearance package and a 5" Rough County lift for the Air Ride Limited. How do you like the Patagonia's? difference in ride? Road noise? etc?