Car is a 2000 Buick LeSabre with 3.8 and 4T65E, 130K miles. The car was owned by an older couple that took it to the dealership for service religiously, so it's been well cared for. It had previously shown symptoms of hard shifting and pump whine. I installed a Trans Go shift kit, new filter and new Valvoline MaxLife fluid and that seems to have fixed it. Now under WOT shifts I am getting a strange noise. I want to say it happened on the 1-2 shift, but I can't remember exactly. Basically when the transmission was shifting, I heard a loud "CCCCHHHHHHH" sound. Not too sure how else to describe it. I shrugged it off since I had never heard it before, but my girlfriend is the primary driver of the car and she said was passing someone and and she heard a similar sound when it shifted and now I'm a bit concerned.
Otherwise, the transmission seems to behave just fine under normal part throttle driving. I'm sure the transmission is on borrowed time, but if there's anything I can do that will extend it's life that will leave more time to save for a rebuild. Has anyone come across this before?
