I'm looking at a 2015 GMC Yukon Denali from a private seller in Sharjah and the car has a bit of a shudder when accelerating from a stop, which makes me nervous about the torque converter. I found a service at https://prepurchasecarinspection.ae/brands/gmc/ but I have no idea if they actually know how to test the 6L80 transmission for the common issues or if they just do a basic visual check. Has anyone here used them for a GMC truck or SUV and can tell me if they put the car on a proper lift and scan for transmission slip counts? I don't want to waste my weekend driving out there only to get a weak report. Appreciate any real feedback.