I'm working on a 2015 GMC with a full exhaust system removal, all is well with the truck and it's happy with no codes then after a 150 miles it has 65mph speed limiter with no messages or codes, then after another 50 miles it's limited to 55. So I'm assuming it's the def related limiters but I have all 3 maxed and the def speed limiter option set to no but im still being limited. It goes away for another 150 miles after a new tune is flashed. Anyone else seeing this?