Hey all! I just purchased my first SRT-10 Ram (2005 QC). I am having an issue similar to what our fellow user experienced here: https://www.vtcoa.com/threads/speedometer-is-off.68872/#post-1316828 My circumstances seem to be almost the same as his, as I purchased the truck with stock rims and the stock tire size according to my build sheet. I saw that people have recommended asking dodge to perform some kind of service on the computer, but can someone tell me exactly what to ask for please? The reason I ask is because I purchased the truck from a Dodge dealer with several vipers and SRT vehicles on the lot, and when I brought this up on the test drive and after the pre-purchase inspection report I had done, they said they did not know how to fix it. They brought up their "Viper Mechanic" to speak to me and he just threw his hands up and looked at me like I was crazy for even asking/caring. I got an SCT tuner from Torrie, but he said that a tuner cannot fix this issue (and installed one of his tunes, which indeed did not fix the issue), so I am curious if anyone knows exactly what I can ask a different Dodge dealer to do for me? Other details: build sheet shows 305/40/22" tires, I just purchased 305/45's but have not had them installed yet. I did the math and the new rev's per mile would be 633.84. The speedo is off a lot more than the other user here, mine is off 10MPH at 75MPH and seems to be off by +1MPH every 10MPH after that. Thanks for any help in advance, guys! I'm pretty excited to start driving it once this whole pandemic is over.