I have a 78' 530i which has had a Euro 3.5 transplant and a few other mods. The problem that I have been having is that the rubber donut (Guibo....Spelling?) between the drive shaft and the Tranny seems to be quite fragile and has resulted in having to be replaced yearly, sometimes less, depending on how aggressively I drive the car. I know that this provides vibration dampening and was wondering if anyone else has this problem occasionally. Does anyone fabricate or manufacture some sort of HD or Sport replacement for this seemingly weak link. Thanks