I replaced the belt tensioner with a new AC Delco unit in June and it failed last week. I attempted to get two replacements (still brand new AC Delco) but they were both DOA when I pulled them out of the box, meaning they had zero tension on them. I think it's likely a poor design, but is there another brand that is considered reliable for this part? I wouldn't worry about it so much except that coolant has to be drained and dealt with because of how GM decided to route the heater inlet and outlet through the freaking thing. That makes changing it frequently extra special and something I'd rather avoid if possible.
My car has 95000 miles.
My car has an automatic transmission.
Hello and thank you for contacting YourMechanic. Shopping around for parts can be frustrating when it comes to specific brands. Some brands are not as good as other brands, however, a low quality belt and a high quality belt should not wear out less than 6 months.
If you have a serpentine belt on the engine, remove the belt and check all of the pulleys for any wobble and make sure that they are in good shape. Put the belt on, or a new belt, and then pull on the belt. If the belt was really tight to get on and won’t move much when installed, then the belt is the wrong size for that engine setup. You would need to be able to move the belt at least 1/4 inch on the tensioner to have the right amount of pressure.
I suggest Napa brand belts or go to the dealership for the OEM belt to keep the vehicle running correctly. If you need assistance with the belt, then seek out a professional, preferably a professional from YourMechanic to help you with a proper replacement of your belt tensioner at your home or office.