My father is giving me his 1999 Buick LeSabre with 100,000 miles. He says he has never changed the transmission fluid. I notice that it does not shift down normally when I step on the accelerator, but it does drive ok. Should I put in new transmission Problem down shifting upon acceleration. Transmission fluid never changed. Is it better to change the transmission fluid in hopes that the problem will go away, or will it likely make the transmission problems worse if I change the transmission fluid? Some people are saying that I'm asking for problems if I change the transmission fluid at this point.
Tuesday, May 8th, 2012 AT 5:54 AM