I'm digging into 105 Giubos as some club members around here have been faced with driveline vibrations. We are down to swapping parts from cars to cars to isolate the source. We have dealt with three different driveshaft specialists to balance parts, and recently two of them have pointed at the donut as being the joker in the game. They cannot mount giubos on their machines.
One of the cars involved started vibrating after the gearbox was rebuilt, and a new repro donut was installed. My own car has a similar vibration after years of replacing/swapping/balancing everything - and a repro donut from Centerline. Hmmmm.
I still have the original Pirelli donut from my car, and will reinstall it just to see what it changes.
I looked at Spruell's site, and they do not sell the German donut anymore. As a matter of fact Paul seems to be winding his business down.
Just for fun, I tried to track down the Mercedes donut that sort of fits. Rockauto has a wonderful catalog, and in some cases it gives dimensions. This
seems to be dead on. (MB 2114100415). However, given the troubles some of you have experienced installing it, I don't think it would help.
Any thoughts appreciated.