I've had this thud with both of the S550s and both of the S197s that I've owned.I have an '18 ecoboost that i custom ordered from the dealer. noticed the "THUD" day 1. still have the thud when shifting into 1st 17k miles later.
if this is a "fixable" issue, that would be great, but I doubt it. i brought the car back to ford shortly after getting it for something (forget exact reason), and the tech manager almost immediately asked if i was there for the clunk sound in the trans. lol.
so clearly, this isnt "fixed" for all 18+ mustangs.... i think its like others say, just a getrag thing. prob because the gears are big, or machining tolerances, or some design flaw.
I did a Magnum XL, Tilton clutch, MGW shifter, and QA1 driveshaft. There’s a whole bigass thread here with several of us that have done it. Not too bad, but not 100% plug and play either.What are the parts needed for doing a Tremac swap ? Did you go with Magnum XL or with 3160 ?