Q: when and how to change transmission fluid myself? on 2001 Mitsubishi Galant

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My car has 195,500 mi. and has never had a transmission fluid change. A mechanic told me to not change it becuse the milage is high and due to never changing the fluid there is probably a lot of seditary deposits that will be shifted around if he drains the fluid, thus possibly causing future transmission problems. I just had all the belts and water pump changed, new spark plugs and timming belt. Now I feel a slight shift when accelerating that I used to never feel or noticed. When I took my car for an oil change at Jiffy lube, they recommended a trnsmission flush costing $125 dollars. What should I do?
(1) Answer
Have you taken your Galant back to who ever did the Timing Belt to test drive the car and feel the 'shift' ? It may not be the trans, it could be a misfire or many other things.
I agree with your mechanic. I used to rebuild transmissions and if there is a heck of a lot of mileage on a trans that has not been serviced for a long time, it IS risky to open it up. This is because the fluid gets thick and dirty and wears the parts. When the new, thinner fluid gets put in the transmission, the worn parts do not operate correctly with the new thinner fluid and the trans, often, will not work correctly.