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Q: When I'm driving get to 30mph the rpm shoots up and doesn't go fast gets to 50 and rpm is over 3 changed all oils

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When I'm driving get to 30mph the rpm shoots up and doesn't go fast gets to 50 and rpm is over 3 When we checked the trans fluid it had grim in it no metal so it could be dirty? or whats wrong transmition or something else

My car has 240000 miles.
My car has an automatic transmission.

A: Considering the mileage on the vehicle, it’...

Considering the mileage on the vehicle, it’s be hard to be exact. The poor fluid condition may be the cause of the transmission slipping or it may be the effect of mechanical issues in the transmission. A good rule of thumb with automatic transmissions is to service them every 4 years or 60,000 miles - whichever comes first. If the transmission has not been serviced within the last 100,000 miles at least, the clutches may be worn to the point of slipping. If you want to try servicing the transmission in hopes it solves the problem, this is the way (hesitantly) I would recommend doing it because of the mileage and unknown service history. Have a transmission flush performed, followed with the transmission pan being removed and the filter replaced. This way, all the contaminated fluid is removed and the filter - most likely clogged with debris - is also replaced. Why I recommend this method is because the trans flush service exchanges all the fluid but does not replace the filter. And, the traditional method of draining the pan and replacing the filter does not remove all the contaminated fluid.

The reason I am hesitant is because of the mileage and unknown service history. Best case scenario, the transmission works fine afterwards. Worst case scenario, the transmission may not shift at all afterwards due to the worn clutches. For these reasons, I recommend the vehicle be taken to a local transmission specialist for inspection.

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