I purchased this 2004 Buick Rainier CXL AWD 5.3L in April of last year (2024). It started making a noise that sounds like a playing card running through bicycle spokes or a metal tinging sound. That is the only way I know to describe the sound so I apologize. It happens during acceleration and continues until I let off of the gas. I have investigated every possible thing I imagined it could possibly be causing this and the only thing I found was a small leak in my front differential. This is extremely frustrating because I do not have the money at the moment to take it to a shop where they will undoubtedly charge me entirely too much money to find or fix the issue if it is even able to be fixed. I know that if it is not fixed it will most likely cause more damages to my vehicle and possible cause it to become inoperable, so I am unable to use my vehicle until I can figure out the cause of this issue. Of course the people I purchased the vehicle from never said anything about this or any other issues before I purchased it from them because they wanted the money. Very frustrating.