Hypertech 3400 Speedometer Calibrator with Color Screen, 5.25 x 2.5 x 9 inches

This worked remarkably well. Recalibrated a 2019 Ram 1500 recently without trouble.Software updates:Installed software updates on a PC without issues immediately after receiving product.Quality:Build quality is sufficient to me. The screen size is awesome and cables are great. Almost went with the Rough Country online unit, but dreaded the thought of having to remove so many panels to install it. Glad I went this route. Much much easier to install. Just remove one panel and connect to two ports.Vehicle install:First hookup was a little tough because of positioning of the green ports under dash. Had to partially remove the panel under steering wheel. Cable length was sufficient to get the job done. Device booted up and recognized my VIN immediately. I did have to tune a few times to get calibration as close as possible (dash & GPS). Recently upgraded to Radar Renegade 295/65R20 (35.1”) tires. Initial variance was 5-6 mph over speedometer reading. After a few tunes, I settled on a tune of 34.75” with only a sporadic 1 mph under speedometer reading variance while driving 50 mph. Close enough for me. Measuring the actual tire height made dialing in the initial settings to start with very helpful. Really like that the unit checks for DTCs and allow you to save settings with custom labels.Overall:Will report back after testing at higher speeds. Shifting is drastically better now. Will just have to remember to return to stock settings before servicing truck at a dealership.Fuel economy update:Extremely pleased to note that I am back to 16+ mpg since lift and 35s because of this calibration tool. Haven’t had any issues described by other reviewers. Will circle back around if anything changes. All good so far.

I kept getting a "The Tuner Could Not Be Updated for the Following Reason: Tuner is Programmed".. It said I needed to return the last programmed vehicle back to stock... But this is a brand new device I have never used.

I have a 2019 Ram 1500 5.7.I installed larger tires, going from 275/55/20 Falken to Michelin 275/65/20 Ltx AT/2 E load. I had a speedometer difference of about 4 mph. After reading many reviews & forums I ordered the Hypertech 3400 from Amazon. It seems some folks had issues in the past with larger tire size calibration messing up the park assist or park sensors. I believe that those instances usually involved larger tires than what I installed. It didn't affect my park sensors or anything else. The Hypertech 3400 was straight forward and simple. I updated it on my laptop to ensure it had the most up-to-date info, and once hooked up to my truck, it took 10 min. or less to program. Using 33.50 as the tire size, my speedometer is spot on now, with no issues whatsoever. I can easily plug it in and switch back to stock parameters if I need to take it in to the dealership for service. Simple, easy, does what it should.

This product will VIN lock to the first vehicle it tunes. The only way to restore it is to connect to original vehicle and return that vehicle to stock settings. I learned the hard way thinking I was getting a good price. Quick google search of the error message revealed what was going on. Pay extra and save the headache. And wait time. There’s no two-day prime delivery on these.

I had seen some bad reviews for similar products but I have used this brand previously so I took a chance on this one for my 2019 Ram 3500 Dually. Product works flawlessly and corrected my speedometer as it should have when compared to a GPS. Simply measure the actual height of the tire when mounted on the vehicle and enter in as the new tire size. Went from stock tire size of 235/80/17 to 37/12.50/17 without consequence. Truck shifts and drives as it should without the approx. 17% difference in actual speed vs. speedometer reading. Hardest part of installation was getting the terminal plugged in under the dash.

2020 Ram 2500 with a 6.4 Hemi - Worked just like I hoped. Took about 15 minutes to calibrate my speedometer after installing larger tires. About 5 minutes to find my glasses and read the instructions, 5 minutes to get my old fat gut under the dash and 5 minutes to set the speedometer. FYI - you can set tire size in 1/4" increments.

Followed all instructions completely. Was able to get it to check for latest firmware updates on my computer and it verified that it had the most current version. However, when plugged into the truck it would only show "looking for computer" and never anything beyond that. According to the instructions, that's not even one of the things it should say when plugged into the truck (not the computer). Have used these products before on a Jeep Wrangler and always had good success. This one, however, didn't work at all on my 2019 RAM 1500 Limited.

I purchased the Hypertech 3400 s/n 2118497 off Amazon for my 2020 Jeep Gladiator w/ 3.6L gas. Its a Rubicon and comes with 33" tires. I put 35" tires on but cant get it to calibrate correctly. I checked my speed before calibrating and the Jeep said 60 when apps on my phone said 65, so it was reading 5 MPH slow (as expected). Tires on the jeep actually measure 33.75 so Hooked up device and input the info (stereo, lights etc off) then ran a test and now it reads 4 MPH fast. Tried inputing 35" and is off 6 MPH. Put in 33" (smaller that actual tire) and its off 3.5 - 4 MPH. Im super frustrated. I updated it online, and tried again, same results. Ready tp take a hammer to this thing. What do I do? I feel like I wasted my money on this thing. I Wrote customer support and they said “ Go down on the new tire size to play with the numbers ” which I’m going to do but it just seems this device should be more accurate. Had I known that I would face these issues to begin with I would’ve stepped up and bought something else.

Item shipped quick and arrived in good shape. Unfortunately every time I attempted for 35" tires on my 2022 ram 1500 resulted in the loss of park assist. Too bad.

Bought this hoping it would fix my problem but only caused more. Flashed the truck and it turn off my park sensors front and rear. Called hypertech to see if there is a fix for this and they said it’s suppose to mention that in there ad. It does turn them off so there’s no way to fix tire size and have park sensors available. They said I would need the inline speedo cable to fix my issues. Can’t return this now so stuck with a paper weight

Not happy. Failed to do what it's supposed to. Terrible instructions. Error after error. Not worth the money at all, a total waste of time (2 hours, not the 3 minutes as advertised). Buyer beware!!!!