look at the rear muffler band clamp, the bottom may be attached but then top may not, causing vibration when taking off from start. can be LOUD.

Before you go throwing yourself into a labor-intensive project, you might as well check to see if the exhaust is touching anywhere. It makes really annoying vibrations if it is making a near constant concact with the chassis for any reason. The vibration due to this is most likely to happen upon takeoff due to the shifting attitude of the car. This could just be a rotted or broken exhaust hanger, and would cost next to nothing in $ or mental anguish. Good luck.

i had a simlar "growl/vibration". When the car was loaded and the back end sagged (no "nivs" heavy springs) it got worse leading me to believe that if i raised the center bearing it should help. I did and it got better, I reccommend to anybody with this "growl" (no nivs) that you load the back end (sand bags etc.), if it gets worse, raise the center bearing, if it gets better, lower the center bearing.

This worked to help me tune the "growl" out of my drive train, good luck

Hi, this is a common problem on the 700 series. It is caused by the center bearing support on the drive shaft. The bearing is rubber mounted and softens with age. This tends to be worse when you load the rear axle because it changes the angle between the drive shaft and the propeller shaft (tends to straighten it out). There is a solution invloving putting spacers between the bearing pillow block and the chassis to increase the relative angle between the shafts. Check archives for center bearing support and you should find the actual instructions.

good luck