I just got done replacing my belt tensioner because it had maxed itself out over the years and while I I was changing my engine belt (that had a tear) I thought it would be a good idea. The belt tensioner pulley was also shaking a bit so why not... I went to advance got a new one, not exactly like the GM one.. now the belt tensioner arm vibrates back and for a bit.. is this normal ? is it just setting itself ? will the shaking stop ? do I need to put the part back in the box and get anohter one ?
Thanks
Chris

 

Did a new pulley and bolt come with the new tensioner? You might want to look at them if they didn't. The bearings could be shot in the old pulley if you are using it instead of a new one.

 

tensioner came with new pulley on it.
Chris