The Questions and Answers below are from a recent article published in The Republican. Chris Garman is the President of Wilhelm Automotive.
Question: I just purchased a used 2004 Buick Century with just about 49,000 miles. Car was inspected and runs well, except after about half-hour in the car. At that point, it begins to shift into gear harder, and lurches a bit. I took it in and had a transmission fluid flush, but unfortunately that did not seem to help at all. What could the problem be and what is the best thing to donext?
Answer: The transmission flush was a good idea based on your issues and its recommended by some manufacturers every 50,000 miles.
Like all automotive fluids, the transmission fluids can deteriorate over time, especially when driven in rougher conditions such as frequent stop and go city driving.
The fluid may be red or brown, but darker colors can indicate the fluid is deteriorated and a burned odor will tell the mechanic there may be more serious transmission issues.
If the mechanic didn't find anything unusual with the fluids, it could have pointed to the problem. Without a complete inspection, it's a little difficult to know for sure. But it is somewhat unusual that a car would have transmission issues at 49,000 miles.
It is possible that there is some other computer control function that feels like a transmission problem. High engine RPM can make a transmission shift into gear hard. Ignition system problems (spark plugs, wires) can also make a vehicle jerk when accelerating.
I would start out with a diagnostic on the computer system, and most qualified technicians have computer scan equipment that they can hook up.
Of course, it's a good idea to bring you car in when it is acting up so the technician can see the issue while it's happening.
Once recorded, they can go back and review all the data and hopefully see what is failing.
Chris Garman is president of Wilhelm Automotive. Reach him at firstname.lastname@example.org.