Review on ACDelco 12609719 Original Equipment Tensioner: Ensuring Optimum Performance by Edgardo Ennis

A squeak can be heard every now and then. So I changed the tensioner, AC belt and tensioner, alternator and belt. all branded ACDelco. The alternator, tensioner and AC tensioner had bad bearings. After replacing all those parts, it still squeaked in the cold (winter temps). I checked all the other wheels and bearings and nothing else was suspicious or rude. I eventually narrowed the noise down to something to do with the belt rather than worn pulley bearings, since spraying the belt with water eliminates the noise. I also washed and degreased all the pulleys. Still screaming. Either the pulley is misaligned or something else is causing the belt to slip intermittently. Eventually I replaced that belt tensioner. I last kept it as it was replaced with a dealer bought ACDelco already about 8 years ago (maybe 35k miles?). I think the squeaking is finally gone. Apparently belt squeak is a really common problem on these Silverados and there are tons of videos online talking about pulley bearings, pulley alignment, belt contamination, belt brand etc. I was misled by a video that showed sideways wobble on this loafer and specifically stated that that was why it was bad. Well come and find out, either all the stock tensioners are bad or the mechanic on the video made a mistake. My bet the mechanic got it wrong. So far I've researched my original ACDelco, this new ACDelco, the new ACDelco pulley itself, and the Gates brand tensioner - ALL FOUR have the same roller bearing wobble. What is the difference with this new one? Why has my squeak finally gone? There seems to be a lot more spring tension on this new one than what I was using. Despite low mileage and good bearings in the pulley, it may have been too old to properly hold the belt. A stiffer spring means a tighter belt, which means less slippage => less noise.