Jumped on this at first but may or not be related. My 2-by may have a similar shudder. I usually notice it on a restart after parking. Spin the steering hard over to try to get out the parking space and WOW! Assumed it was a slipping belt...
2007 Black Lariat SuperCrew. 6.5' bed. Tows a 5000 lb Jayco Ultralight TT and the DMC.
1999 GMC Suburban. Sadly, the Sub died at 196,000 miles. RIP.
1981 DeLorean. Tows nothing, holds nothing. Causes time rift at 88 MPH.