I installed the driveshaft along with a bunch of other parts: long tubes w/3" exhaust, Ford toe link bearings, BMR lowering springs, cradle lock out, jacking rails, vertical links, poly motor mounts, spherical bearings for the lower control arms, Fore triple pump level 4 for e, and a gen3 Whipple. I had what felt like a slight shutter/vibration during initial acceleration, but because I changed so many things at once, I didn’t know what was causing it. After I drove the car for a little while, I figured I’d try to narrow down what was causing it and started with the driveshaft. I dropped the exhaust and installed the stock driveshaft. Because of the way the exhaust goes together, I spent a whole day getting everything lined back up. When I tested the car, it drove the exact same way. Because there was no noticeable difference between the cf and stock driveshaft, and I don’t race the car, and I don’t want to take that exhaust off again, I decided to sell the cf driveshaft instead of it sitting in my garage. If it doesn’t sell before I have to drop the exhaust for some reason, I’ll put it back in. Thanks for the question. JackWhy do you sell it ??? any vibration ???