The following is the change history log for XRT Pro Tuners that was previously hosted by H&S Performance before they closed down. The information listed is for tune file versions used by the 6.6L Duramax LML.


Current Version: 6.6.42


6.6.42 Sept. 10, 2014 – Additional system and speedo calibrations recognized


6.6.41 Apr. 29, 2014 – Additional system and speedo calibrations recognized


6.6.40 Feb. 3, 2014 – Additional system and speedo calibrations recognized, Fix implemented for 2013 and 2014 Customers losing cruise control functions


6.6.39 Oct. 31, 2013 – Additional system calibrations recognized


6.6.38 Aug. 19, 2013 – MCC software supported, Adjustable tire size added, Adjustable gear ratio added, Low boost fueling option added, Fuel tank configuration option added, Speed 

limiter removal without affecting other systems


6.6.37 June 19, 2013 – Internal firmware updates, Additional calibrations recognized


6.6.36 May 20, 2013 – Calibration 12644970 recognized


6.6.35 May 13, 2013 – Calibration 12655930 recognized


6.6.34 April 18, 2013 – Calibration family 12645069 recognized


6.6.33 April 10, 2013 – Street series tuners updated (1031)


6.6.32 March 20, 2013 – Additional 2012 Van calibrations recognized


6.6.31 March 8, 2013 – Turbo vane modifications to remedy exhaust “hiss” during idle on all emissions removed tunes, Fuel pressure deviation thresholds modified to combat low fuel 

pressure limp, Urea system messages modified for emissions removed tunes, Additional 2013 Van calibrations recognized


6.6.30 Feb. 18, 2013 – Additional 2013 & 2010 calibrations recognized


6.6.29 Feb. 4, 2013 – Additional 2013 calibrations recognized


6.6.28 Jan. 24, 2013 – Street series firmware suported (version 1030)


6.6.27 Jan. 9, 2013 – Firmware 1023, DPF delete modified to High Sulfur text, Log files added, Auto detect firmware update added, SD card communications updated, Power level names 

changed – Stock, Tow, Street, Performance


6.6.26 Dec. 14, 2012 – Calibration family 12645012 recognized


6.6.25 Nov. 27, 2012 – Additional 2012 and 2013 calibrations recognized


6.6.24 Nov. 20, 2012 – Show Settings tech menu fixed


6.6.23 Nov. 15, 2012 – SD communications updated, Show Settings screen modified for more info, Firmware 1.02.2


6.6.22 Oct. 22, 2012 – P249D fixed for 2013 DPF Present Tuning


6.6.21 Aug. 23, 2012 – 2013 models supported


6.6.20 July 24, 2012 – Additional 2012 calibrations recognized


6.6.19 June 27, 2012 – P111D DTC fixed for 2012 DPF Present calibrations


6.6.18 June 14, 2012 – New GM system section 12644991 family recognized


6.6.17 June 11, 2012 – New GM system section calibrations recognized


6.6.16 May 30, 2012 – Firmware 1021 capable, Calibration families 12645016 and 12647082 supported


6.6.15 Apr. 13, 2012 – LGH DPF Present bug fixed


6.6.14 Apr. 5, 2012 – Additional factory calibrations recognized, Key seed bug fixed


6.6.13 Mar. 27, 2012 – Additional factory calibrations recognized


6.6.12 Feb. 13, 2012 – Limp condition caused by low fuel rail pressure fixed


6.6.11 Jan. 12, 2012 – Transmission reset option added


6.6.10 Jan. 5, 2012 – P0188 DTC Wild HP/DPF removed addressed


6.6.9 Dec. 3, 2011 – 12644995 calibration family supported, P0188 2012 LGH addressed


6.6.8 Dec. 1, 2011 – 12646362 calibration family supported


6.6.7 Oct. 31, 2011 – 12645001 calibration family supported


6.6.6 Oct. 24, 2011 – 2012 calibrations supported


6.6.5 P0188 LGH DTC, 2012 LML calibrations supported


6.6.4 New GM Calibrations recognized 12644998 12645002 12645003 12645015, LGH capable


6.6.3 New GM Calibration recognized


6.6.2 New GM Calibration recognized 12645020…


6.6.1  Initial release software