hello, I've owned hp tuners for about a year and this is all still rocket science to me. I put new gears in my truck it is 1999 chevy suburban 7.4l 4l80e on 40's (they measure 39.5) and switched from 3.73 to 5.38 gears. I changed the table but no table to change tire size any more? my speedo is way off it says im going faster then I am. I dont have a current log of truck but can get one in the day. Any help with this is appreciated. I'm not looking to have someone do it for me more or less explain what or where i'm wrong. Not that it should matter but truck has also been swapped with a np205 with a toner ring put in I think the toner ring was 41 count cant remember it is what ever it was stock ( just 1 vss instead of 3 or 4).