For those that have not followed my thread, I have a 68 Imperial with some engine work on the 440, and a freshly rebuilt transmission. I finally got the chance to take the car on a freeway drive with limited traffic, so that I can try some a bit higher cruising speeds. I did not try full throttle accelerations, not enough room for that (plus, I have decided to rejet my Ederblock AFB on the secondaries, so I know the performance is not all there yet). However ... As I was exceeding the 2800-3000 rpm range (85-90 mph, speedo reads about 8 or 9 mph fast in this range), a high speed vibration was felt. When I went a bit faster, the vibration seemed to disappear. At 100 (3200-3300 rpm), this vibration was no longer there. The frequency is too high for it to be tires. I do not recall having this vibration prior to the recent work. My guess is that going faster yet, the vibration will not be there.
Question: Could the people that rebuilt the transmission have assembled the driveshaft wrong? Short of removing the driveshaft and having it rebalanced, is there something that I may be able to do that is easier? I have never had to deal with this before, and I am not sure where to start.
Question: Could the people that rebuilt the transmission have assembled the driveshaft wrong? Short of removing the driveshaft and having it rebalanced, is there something that I may be able to do that is easier? I have never had to deal with this before, and I am not sure where to start.
