High vibration at deceleration with my Triumph Herald 1969 Convertible

[akoum]

Hi there,

I own a Triumph Herald, 1969 Convertible, 1360. Since couple of months I’ve noticed high vibration when not accelerating or decelerating, When i accelerate the vibration disappear, the vibration also disappear when speed goes below 60km/h. I checked the driving shaft screws, all tied up well. I would really appreciate it to have your feedback.

 

[johny]

Hi, first I would check the two universal joints in the propshaft and its sliding joint (if fitted) - see if there is any free play rotationally and side to side. There should be none in the UJs and only a little in the sliding joint but even if there isnt the propshaft could still be the source of the vibration. What you describe is very typical of an out of balance propshaft and if its original then not surprising after so many years....